So just because Google hires researcher and gives them resources, their publication is somehow worth less than Microsoft paying outside researchers?

Why is one somehow superior than the other? Both are publishing papers and pushing academia forward, why does it matter where the researcher are doing their work?

Frankly, when I read a machine learning paper without looking at the list of authors, it is impossible to tell whether it is written by "corporate researchers" or "actual academic researchers". I'm not sure the distinction you're making is really helpful. As long as the research is published openly, peer-reviewed, discussed in conferences, whether the researchers work for the company or for a university does not make much of a difference.

Most of these "corporate researchers" were top of their field in academia before joining Google, Facebook, Microsoft. Furthermore, Google also funds academic research [0]... I'm not even sure where you're getting all your information at this point.

[0] https://ai.google/research/outreach/faculty-research-awards/...

To be fair the boundary between academic and industry research is quite gray now - lots of collaboration, many PhDs doing internships, etc. Still, it's true MS is not given enough credit.