Well, we really don't know their methods in details and they will never share their research details in public
This and the part where they won't endorse code auditing reminds somewhat of the open-source / closed-source debate around security (AKA, "Security through obscurity"). That certain developers choose to not reveal the source code for security reasons, which is completely debunked, as most of the times cyber attacks don't happen after thorough research on the code, but on techniques that are source-independent.
My point was that if everyone who used bitcoin stopped using things like centralized exchanges or wallets like Wasabi or Trezor which all directly fund these blockchain analysis companies, then that would cut off a large part of their funding and many would cease to exist (not to mention making general blockchain analysis much more difficult since you would no longer have KYC linked addresses and such).
Chain analysis companies are getting funded with millions of dollars from the US government, so it isn't just Wasabi's and centralized exchanges' fault here. But, sure, if half of the Bitcoin userbase stopped using Binance and switched to self-custody, they'd start panicking.