Using TOR does not make you a criminal.

Using TOR for illicit activities like selling drugs does.

Many Clearnet websites like Facebook, BBC, NY Times, Keybase, ProtonMail use .onion links; the website I'm using to write this has a .onion address, even Pornhub has a .onion mirror. The reason they have this available is so people in countries like China, Hong Kong, Belarus, Russia or authoritarian Governments have the ability to access them provided they can get the Tor Browser Journalists, activists or anyone worried about their Government spying on their social media use the Belarusian athlete, Krystsina Tsimanouskaya expressed concerns about her country during the 2021 Tokyo Olympics she is seeking asylum in Poland.

Tor was originally funded by the U.S. Navy to secure communications between allies. Privacy is power over your information, to understand what type of digital trail you leave behind and gives the ability to limit the trail or who can see the trail.

Using Tor should depend on your threat model, what do you want to protect, and who do you want to protect it from?