[foobarchu]

They start blocking any fingerprint that looks like you're hiding it. Similar to sites blocking known Tor exit nodes and proxies.

[FridgeSeal]

The point is that the fingerprint looks like “the generic fingerprint”, blocking that would be pointless, because it’d block a massive number of completely valid users.

[mycall]

It doesn't have to be blocking fingerprint, just whatever garbage data that works and the cat/mouse game will continue as usual.