Very true.
Like your Grimrail run, in most cases people won’t call you out no matter how bad your DPS or how often you chain-die to mechanics. It’s better to move on than risk getting banned.
But the anxiety and phobia make me want to avoid the risk of getting called out at all costs. Even if no one is calling me out, I hate the feeling that it could happen at any time.
I would do Mythic Zeros if they were queue-able and rewarding. They are reasonably tuned and only have a couple more mechanics than Normal/Heroic.
No one technically needs to upgrade their gear.
But then again, a successful MMO should make all types of players feel like they need to upgrade their gear, including solo and open world players.