Been looking for an alternative to gmail and out of all the ones I’ve looked at protonmail seems to be the best one.
Depends on your definition of legit : https://lemmy.ml/post/79956
And as always it depend on your needs. If you need to hide communication within a group of people, you all need to use protonmail, otherwise the mail comes out of protonmail server without more security than any other mail provider (from what I understand).
If you want to fight centralization of services, protonmail is already really big, and did not create a federated solution to their encryption method, so they are not helping. Then you should find a local, or at least small independent email provider.
If you just want to be outside of the US, protonmail is great for you.
If you are a political activist of any sort, and fear your government, then recent history showed that protonmail don’t want to protect you from this kind of intrusion.