This isn't true. It used to be true, but advanced fingerprinting done is measuring certain metrics that Tor Browser are not always blocking against. On fingerprint.com, it will give you a hash and say how many times you've been there before. For me, it said I had been there once. I closed the browser, came back, and had the same hash and it said I had been there twice. I did this tests multiple times and in multiple ways. Notice how this person didn't post any screen captures of from fingerprint.com showing that they have supposedly visited 1000 times or whatever would be expected if Tor Browser had a fingerprint that was consistent across all users. I posted very clearly the problem, and some people replicated it, and some people couldn't, and the problem may or may not vary across distros. It's also possible some people could be lying. But yes, I tried to post this on privacyguides forum and they made it incredibly hard to post it, then deleted my username, and it was strange, and other people have had strange experiences.