I think the CS degree validity question depends on the person and the institution. I have interviewed programmers from CS programs that did not know even the basics of programing, not to mention the more advanced topics that we should know. I also know of programs that are producing pretty well rounded and knowledgeable students with a 4 year degree. So the normal YMMV must be applied.

I also think the same holds true for self taught programmers. I am self taught. Early in my career (decades ago) I was using perl to process some large text files. I was building a string of relevant information like $x = $x + "some value".

So this was wrong on so many fronts. After 25 hours of running I figured something was wrong. Okay, so I'm a slow learner...

I preallocated the string and the program ran in less than 20 minutes. Now of course a string was an inappropriate data type as well. I learned a lot at that point and starting thinking about internal representations of data structures and other concepts.

Usually here is where we observe Dell, Gates and Jobs didn't finish college. But that's more about business than engineering.

And even if it wasn't, one could retort that Brin, Page, Musk, Nadella, etc. did, and in fact, did graduate level studies. It's a complex question.