I don’t know what ActivityPub is.
I think that it is a lot to expect occasional users who are knew to discourse to know to:
- Set up notifications
- understand the tracking/ watching preferences for categories and tags (as this isn’t the usual terminology nor UI for managing preferences
- know that they also need to decipher that email page with multiple drop downs
But I agree about the amount of settings. One solution would be to allow administrators to reduce the amount of settings that are available to users. I’m not sure all are needed in all forums. This is a truly remarkable software with all of the options to customise but allowing administrators to reduce options for users e.g. turn off navigation choice or others might really help.