Linux is started with the aim to replace any other operating system. But what exactly are alternatives to Linux? The best practice method in developing a non Linux operating system is defined by hardware manufactorer. They are using two principles in combination: first, the operating system will run only on their own hardware but never on the competitors hardware and secondly the operating system is published under a proprietary license. This strategy was common 40 years ago and even today it's the normal case what the hardware companies are doing. Does it make sense? For the companies it is useful but for the customer it's a nightmare.
Let us give some examples: IBM has released in the 1960's the mainframe operating system System/360. This software was only able to run on IBM hardware but nowhere else. Apple has released a nextstep based operating system which is tailored for Apple hardware. Sony Playstation has invented it's own operating system, the same is true for the SunOS workstation in the 1980s, the HP Workstations in the 1990s and the famous Windows Operating system runs only on desktop PCs too, but not on server hardware.
So why have all these companies an individual tailored operating system? Because standardized software would reduce their income. If the Sony playstation system would be able to playback xbox games, if Apple software would run on IBM PCs then the world ends. Which means, the profit for the companies would be lower, and the customer would become more important. This is what the hardware manufactorer are trying to avoid. They are argue, that the customers doesn't want a standardized operating sytsem, but it's not the wish of the customer but the need of the manufacturer.
Let us analyze what the plan of IBM, Apple, Microsoft and all the other tech companies is. Do they want to produce innovative software which fulfills the need of the mainstream? No, they want to make profit. And this is only possible against the customer. They are inventing lots of incompatible operating systems which are restricted to their own hardware and which are sold for money. They are able to do so, because the customer is in a weak position. It's the same situation like in the early videorecorder market in which VHS, Betamax and Video 2000 have compete against each other. If the customer has bought a Betamax system he can't playback the media on a Video 2000 recorder. So he has to buy the Video 2000 hardware too which will increase the overall sales.
In short, this is what Apple, Microsoft, IBM and all the others are doing. Linux would solve the issue, Linux is a standard which runs everywhere and is very consumer friendly. .And because of this reason the companies hate Linux. Let us take a look at the websites from larger hardware companies. They are ignoring Linux or they explain why Linux is a bad idea. This description has no technical reason but it has to do with the company's policy. Boycotting LInux is a longterm strategy which is run by every hardware company. It's done against the customers need. Let us compare the situation in a 1:1 table.
Linux: open source, runs on different hardware
non-Linux: closed source, runs on a single plattform
The Microsoft Windows operating system is located somewhere in the middle. It is more open than the Mac OS X operating system, because Windows 10 can be installed on different hardware. At the same time, it is not open enough to compete with Linux. Microsoft Windows can be interpreted as a transition from hardware controlled operating system which was common in the IBM and SunOS area, to open systems which is Linux. From the point of view of very closed hardware companies, Microsoft Windows is too open. Apple doesn't allow the user to install Windows on the Apple hardware, even it's possible from a technical point of view. The same is true for some propriatery workstations made by HP. Only the HP-UX system is allowed to boot these machines. Linux can be imagined as some kind of improved Windows operating system. It runs on more hardware plattform and the costs are lower. Additionally the sourcecode is available for free.
It remains the question open why the customers are not argue against the hardware manufacturer. The reason is, that a company like Apple doesn't only sell a computer it sells an ideology. The customer identifies with the needs of the company. He thinks, that after buying the latest MacPro he is part of the Apple family. And then the customer defends the needs of the company against the public. That means, the perfect Apple customer is no longer an end user but he is interested in making Apple a success. That means, he will argue, that a Mac OS X propriatery operating system is superior to an open source system which runs on every piece of hardware. The customer has adapted to the ideology of the hardware company and he feels stronger with this ideology.
In contrast, Linux fanboys are normal customers. They are arguing against the hardware company. Linux user are not interested in a certain computer from Apple, HP or Dell but they are interested in running software on the system. From an abstract point of view, the today's computer market is driven by customers who are identify themself with the companies. Very similar to the hifi market in the 1980's in which the customers of Pioneer were different from the customers of Kenwood. What the customer is doing after buying a product is to tranform himself from a customer who argues against a company into a loyal part of the family. As a consequence the customer will defend decisions of the company for example the decision that the operating system runs only a single hardware but nowhere else.
What i want to explain is, that Apple, IBM and HP doesn't have real customers because the enduser doesn't argue against the manufactorer. The customers are usually on the same side like the manufactorer and this prevents that they are installing Linux on the hardware. Linux can be understand as a customer ideology which is against a certain hardware manfucatorer. The famous statement of Linus Torvalds against the nvidia company is a good example. An Apple customer would never argue against the hardware in that way.
Let us define what a true operating system is. A true operating system is independent from the computer hardware, fulfills the need of the enduser, costs nothing, is available as open source and is equal to a standard. The only operating system which is available today is Linux. All the other software on the market (Windows, HP-UX, AIX, Mac OS X) are not operating systems but ideologies which allows the customer to identify with the needs of the hardware manufactorer.