There is KYCP which has analyzed quite a few Wasabi coinjoins and has found a bunch of weaknesses regarding collaboration and address reuse (in both inputs and outputs!), such as this one. What is your input on this?

That's not Wasabi fucking up, that's Wasabi users fucking up.  Wasabi, they fundamentally, are not in a position where they can go and prevent people from installing the same seed in multiple wallets at once and using it in multiple wallets at once.

How's that relevant with the coordinator allowing address reuse

and the other weaknesses during coinjoin that are presented above?

What "other weaknesses" are you talking about?