Pretending the current iteration of twitter is anything remotely comparable to what existed before is pretty ridiculous. Other than grok, which is by far the worst of all the flavors of models out there (and very technically, made by one of musk's other companies), there haven't been any new features in years, even down to the terrible UI/UX has barely changed at all, and the particular "slant" the site takes in addition to the swarms of boosted bots out there rendered the site practically unusable for me in a very short period of time. I honestly don't understand people that still use it or what they could possibly get out of it. If there was any honest reporting about DAU/MAU I'd bet a large part of my paycheck it's way down from pre-musk levels.
Those are due to deliberate policy changes from Musk to boost engagement of his right-wing sycophants, not due to any technical failings. From a strictly technological point-of-view, Twitter works just as well as it did pre-takeover, and certainly did not catastrophically collapse as many predicted.
I would categorize what happened to the site and it being rendered unusable by anyone even halfway serious as catastrophic - but perhaps my bar is a little higher for the "smartest man in the world" than "I can still get a 200 response from the site" (which actually is also down, in terms of outages).
I agree that the site is barely usable, but that's entirely due to a shift in Twitter's userbase caused by top-down policy changes (e.g. boosting right-wing spam), not any engineering shortcomings.
If Musk had never purchased Twitter and Jack Dorsey performed the same reduction in engineering staff, I doubt the site would be materially different from how it was pre-Musk.
That's because software is immortal. It will continue to run even if you do nothing. What happens, though, is that stuff around it moves.
Of course twitter still works. Even with 0 engineers, it would still work. That's never been the goal of a software company. I can compile Mario 64 right here, right now, decades later. Should Nintendo just go home? Call it quits? Of course not.