Why are some members avatars totally blurred out?

Various reasons.

If the comment or reply is hidden, the pfp is blurred because of the language. If the user is a minor, the pfp is blurred. Also the age and gender is hidden.

I think there's one more reason, yet I can't remember what it is.
Something to do with comment rating perhaps.

They have redone the ratings of pretty much everything, including ratings of groups and even your own default settings.

Yeah a lot of people blocked me after the US election lol

Or you've muted them

Minors.

The algorithm determines your account as containing adult content not suitable for their age. Therefore, you get automatically blocked.

There is also the case of any avatars of accounts that might be deemed adult, or used adult avatars in the past. They get auto-blurred.

Many blurred ones are underage users.

If there profile has too much fet*sh material, that will cause it to be blurred.

I think another one is if they had too many reports or downvotes.

I had always assumed those were people I had offended who had blocked me, lmao.

Pervertd

In sitting up their account, they have blocked a group or groups that you are in, like males over 50

I should make a blurred avatar

FBI has them under surveillance.

Because you’re creepy