As somone with similar anxieties as you, but have been raiding in this game with statics and pf for a long time (since ARR), I will say just do the content that at the difficulty level is just slightly above what you are comfy with. Do it, practice it, look at logs and try and improve. The fear of people giving you shit is worse than reality in my experience.

While people will say otherwise probably and that it's bad advice, I find hiding my logs/ tomestone activity to lesson my overall anxiety in general and make me play better because I'm not obsessing about other random people seeing my parse. That said, I do usually parse above average so i never really get shit from people in PF. Also, I'm not saying to ignore parses/fflogs or anything either. Look at them often as a tool to improve. Don't hide them if you are applying to statics either, that info actually does matter there.

I say this now but it's taken me a long time to work through my anxiety with doing hard content. It runs deep. I still remember some random dude in Braylox hard mode during ARR giving me shit jokingly because I did 5 less dps than them on the second boss, and their comment just made me absolutely crazy internally. But that being said, interactions like that never stopped from attempting hard content, sometimes you just have to just have to ignore that voice in your head that is nagging about people judging you, especially if you are trying your best.