That's one reason to have research universities. Another is to ensure that research results are publicly available. This is quite important in AI, where a hand

That's one reason to have research universities. Another is to ensure that research results are publicly available. This is quite important in AI, where a handful of large companies could take control of a critical technology, and nobody outside the companies would have any understanding of it. A third is to ensure that all types of research are considered. One of the results from the economics literature is that using algorithms to set prices can lead to the same prices you'd have if the firms colluded. It's plausible that some companies would be hesitant to have their high-salary employees do that type of research and share it with the world (but also plausible that they'd be happy to do that type of research and keep it to themselves).