I just don't buy this. There is literally no way to build a CUDA clone without testing output against both your clone and CUDA itself.
With this reading, EULA's have effectively banned cloning any form of software.
Not necessarily. You might be able to get by only testing against third-party products that use CUDA.
We did something like that at Interactive Systems Corporation in the '80s when we wrote a 286 Xenix emulator to run on 386 System V. If I am remembering correctly, we never actually had a 286 Xenix system to compare to. We just had a bunch of system call level test programs, and a few big applications like word processors.
The difference being that they didn't have a second team dis-assemble and actually reverse engineer the product to write a formal spec for how it functioned. Instead they did A/B testing to ensure that the output of the known product produced the same output as the reference implementation, reportedly without examining how the black box worked.
On the other hand at a certain point it becomes a monopoly with a negative societal impact.
You've gone from "Drug manufacturers get patents and a period of exclusivity" to "Patent and exclusivity, and also protection from generics for the brand's life", but patents can be applied for at any time during a drugs development, including before it's ever been synthesized (e.g., theoretical manufacture via computer models) but the exclusivity is only a U.S. FDA marketing feature. Patents on a drug could expire before the exclusivity, so a competing manufacturer could create a secondary brandname drug and sell it overseas during that period. I'm really confused as to where this EULA would even fit in, since you've just moved the goalposts with your "even after" clause.
If the FDA had some kind of deterministic human trial of a drug, like some dystopian lab-grown identical human clones, of which drugs were trialled on and some company B was able to obtain a set of these clones from company A that had some kind of defect of which the drug was targeting as a cure or remedy for, and then used those proprietary clone models in order to test their clone drug against, we might have some kind of metaphor worth arguing against, but we don't.