I am trying for the life of me to understand how to mute/ignore when the person you no longer want to hear from has their profile set to private. I have googled it and it just comes up with other forum posts from people asking the same question.
Does anyone know how I can do this?
Click their profile icon, view activity, it will take you to where it says their profile is hidden.
Copy the user battletag from the URL.
Heres mine as an example:
https://us.forums.blizzard.com/en/d3/u/TheDarkJedi-1970/activity
Click your user profile icon (upper right), click the bell → Preferences → Users (left) → Add… Enter the battletag.
Got it! Thank you so much.
Yeah it’s annoying that there isn’t an easier ignore function on a hidden profile.
MAKE IT HAPPEN BLIZZARD
Yes I agree. I had to, as if you reach a point in your life where an online forum is stressing you out, then for the sake of your health you need to, well that was me.
It is super easy to ignore another poster on this forum. Just go to your forum preferences. Click users. Then add the name to the ignore list. It even auto-populates names as you type in their battletag so you do not even need to know their full batteltag.
Right before the release of a ‘remaster’ of one of the most iconic ARPGs is bound to be stressful for anyone who loves the game. 
Most certainly, it’s like replaying our youth, it’s like being able to literally play nostalgia, just with a face lift.
I probably added 20 people to ignore on here in the past month. Definitely made the forums better.
It is a similar feeling for me as when Oldschool runescape and classic wow released. I am glad a lot of the games I loved as a kid are coming back in some form.
I just hope this launch goes better than warcraft deforged.
People will complain that the forums should only have FFA posting and will threaten to leave if you give others the option to not see their posts. 
I will gladly show them the Alt+F4 door.
I get a little trophy every time I discover someone has added me to an ignore filter. I do not return the favor, though.
This is the most useful thread I’ve seen in this forum since February.