No, they are probably breaking the rules - and the rules are not being enforced. That's the point.

If this were merely a company using a regular tax deduction there would not be much of a story.

The story is that these GPUs are not being used for research but Ops and therefore should be subject to taxation.

Its not clear, the IRS will presumably decide if, for example, Zuck gets an R&D tax deduction from his salary because he contributes to code, which no other large tech company has tried to claim.