matchboxbananasynergy
Totally agree with you - I meant social websites or other websites that are not privacy-friendly by design. If someone is using Tor to become anonymous then it doesn't make much sense to login to a website that knows your real identity as they will know its you. There are, of course, many Tor-friendly websites like secure email providers that one can use with Tor without compromising their privacy.
Its also mentioned on Privacy Guides: https://www.privacyguides.org/advanced/tor-overview/#encryption in the Caveats section "Nor Tor protect you from exposing yourself by mistake, such as if you share too much information about your real identity" (in other words - if you, for example, log to a social media or other non-privacy friendly website that already knows your real identity and will know it is you behind the Tor).
I think the best practice would be using Tor Browser for general browsing, websites that do not know your real identity, as well as logging to Tor-friendly, privacy-respecting websites whilst using Vanadium (or other preferred browser) for social media, online shopping, etc.