How is that lukewarm? Sounds like first class support if they have a dedicated onion address and not just let you connect to the regular clearnet. Or is that address only in that old blog post and not mentioned in places you'd usually look? It's a bit unclear to me.
It's lukewarm because what less could you do besides not support Tor?
Tor is mentioned on their homepage in the bottom menu under "Onion Site". However, this menu link redirects to their Tor placeholder page, rather than directly to the Tor service: https://protonmail.com/tor
> It's lukewarm because what less could you do besides not support Tor?
Alright then, what more do you want them to do? Spend millions in court fighting every warrant issued for their users and go bankrupt defending criminal activity?