The reason blacklisting is wrong is a similar reason mass surveillance is wrong. It's not a new debate. You can't just label everyone guilty until proven wrong.
The whole concept of "taint" is a huge sliding scale. Being gay is illegal in some countries, let's reject them too! And anyone who had sex before marriage must burn in hell, right? And the guy who was speeding yesterday, you wouldn't want to be associated with that
wreckless behaviour, right? And freshly mined Bitcoins? Those are the worst of all, let's not associate ourselves with the environmental impact fresh Bitcoins have.
If you look deep enough, you'll find a reason to taint
every piece of Bitcoin out there.
Mission accomplished, Bitcoin is dead.
I think you put it much better than me; I was trying to say: Sure, they are free to introduce blacklisting; it's part of what Bitcoin's freedom allows you to do. But be aware that you're going to destroy Bitcoin in the process, especially if you normalize it and set a precedent that other wallets might follow.
When wallets announced their support for AOPP, we didn't all sit around and wait for them to implement it before complaining and getting them to reverse their decisions. When certainly payment processors announced they would start requiring KYC from all users, we didn't sit around and wait for them to implement it before warning everyone to switch to different processors. When BCashers announced they were going to fork bitcoin and launch a shitcoin, we didn't wait around for it to happen before warning everyone about said shitcoin. I don't see why Wasabi would be any different. They have clearly and repeatedly both stated their intentions and defended those decisions.
I do think that technical solutions are a more sure-fire way method to make sure fungibility and privacy is maintained in the future (more discussion about this currently
here), but it's good to list the precedents where the 'market' / simply the public voice had significant impact on Bitcoin's development.
A few notable examples so far happened in 2017:
BCash,
SegWit2x, and the SegWit UASF.
And then of course
AOPP (
2021) - potentially, the market will this year be able to get businesses to drop blacklists and anti-fungibility implementations!