This just gave me the idea to make a website where you put in a transaction ID and it gives you a 'taint score' (just like those other blockchain analysis services), but this score is simply always 100%, with a nice green background and informative text saying 'This UTXO is wonderfully clean; it is yours if you have the private key to spend it and you can send it anywhere you like.'..

This is actually not a bad idea, but keep in mind that some psycho or regulators could sue or shut down your website you for not providing exact information like it is shown in other analytics services.
You should be fine as long as you add information in footer or in about section that website is created for fun purposes, and that you are not responsible for any coins being frozen on exchanges.
Let's get back on Wasabi wallet topic.
They answered best they could and we can't expect them to change course now when they decided the route they are going.
We can still support the idea of alternative coordinator or some Wasabi fork that would work without any censorship, but someone needs to take risk with this.