While watching the level indicator is part of the strategy, there should be no reason someone else object to you shutting yours off. Probably will never happen because few people would use it for the programming effort involved.
As far as accidentally being left on; it would reset every time player logged in.
E&P. Please add an option to turn off and on experience gains. You added a close to lvl notification shouldn’t be much harder to add this imo. I believe this could be use at times to allow for better use of titan flags. I’m in a situation right now where I can’t play any lvls or do any of the quests without lvling up because if I do I will lvl up and waste the titan flags. I’m sure other people have similar experiences. Just an idea. Thank you.