... were great, because no such innovation was available. All the technology available today, wasn't invented in this period. What was common instead were normal computer technology plus some philosophical books about how to realize Artificial Intelligence in theory. It was even unclear if a chess computer would be able to win against the best human player. The general understanding about AI during the 1990s was, the same like it was formulated in the famous lighthill report. Basically spoken the idea was, that even some expensive AI projects were started at US universities none of them has resulted into something useful.
The only place in which robots in the 1990s were available was the cinema. In blockbuster movies and of course in the star trek series, many examples were shown. But again, none of these things were build by the researchers.
From today's perspective it is known, that the during the late 1980s, the Honda company has developed humanoid robots. But, during the 1990s the internet was not widespread available so even computer experts were not aware of it. It was common sense, that no one has tried to build walking machines because it is too complicated to realize. What was known in the 1990s were some examples for expert systems. Some of them were described in mainstream computer journals. Also it was known, that for playing chess or tictactoe some sort of Artificial Intelligence is needed. But it was unclear how exactly such technology can be realized.
From today's perspective the 1990s have much in common with the stone age. AI was something not invented yet and it was imagined that it will take 100 years or longer to build it. Only to get the figures, the plot of star trek TNG plays around 300 years in the future. And exactly this was the estimated duration until biped robots are build.
Perhaps one surprising insight is, that in the early 1990s robotic competition were not common. From a technical perspective such robots can be realized with 1990s technology easily. But at this time, no one has seen a need for doing so. What was common instead was to program smaller programs in prolog and lisp. For all home computers and PC a compiler was available and some books were available about the subject. What such prolog programs in the 1990s were able to do was nearly nothing. Some more advanced software was able to solve logic games, but most of the programs were created as hello world examples.
With today's knowledge it is possible to identify some advanced projects in the 1990s not mentioned yet. For example the MIT Leglab has built in the 1990s lots of walking machines. But again, the Internet wasn't invented so no one was aware of it. That means, even if they have build these machines and published papers about it, computer experts, and hobby programmers as well simply never recognized it. Or let me explain it the other way around. Suppose a time traveler would visit a larger university library outside of the U.S. in the 1990s and will read all the books He won't find a single piece of information about the MIT robots, the honda asimo project or any other advanced AI project from this time. Sure, if the imagined time traveler is visiting the MIT library and knows which paper he needs to read then he will find the information. But without such an advantage he stays completely clueless.