Systems matter, 'finance' (whatever that even means here) isn't a single system. People matter, and if you whack specific individuals here (if you can find them), entirely different ones will spring into their place.

near as I can tell, these kinds of messes happen - period.

The reason for the condescension is you seem hell bent on assuming 1) there is such a better system that exists, or can exist, that doesn't make an even bigger mess, but don't seem interested in giving a pointer to it 2) that there were specific individual actors that 'did this' and can be identified, and that can be nailed down without new ones popping up in their places. Aka, there are specific bad guys who made this happen, and if they had been stopped, it would not have occurred.

Which near as I can tell, if they exist, even they didn't know they were those people at the time.

It's a never ending cycle that can be improved but not eliminated, and most of the improvement is after the mess has occurred.

If you go after the people involved with a purely punitive mindset like what you seem to be advocating, it also makes everyone hide everything they are doing everywhere even more (good or not, since they can't tell how it will turn out in the end and be retroactively judged), so it is even harder to figure out you've got a problem somewhere until you have an even bigger smoking crater. There were definitely people acting in bad faith and committing clearly criminal actions. There were also the majority of people along for the ride. There were also huge market forces, including all the normal folks signing up for insane mortgages.

Blaming it all on 'finance' is just silly.