I think that people who regularly mention users will automatize clicking the “OK” button and that the warning remains useful. Maybe you meant to put @team (and not notify everyone ). But perhaps having an option to turn those off would be nice for some.
Well, this is for sure, nevertheless remains a frustrating thing for a power user because he already knows that if he mention a group it will notify all members and he already knows that he is dominating a topic (this happens especially when a power user write some documentation modifying the OP and add a reply to inform the rest of the community what he added/delated/changed and why).
Let me reformulate the feature request as “disable those messages related to a possible bad behavior of the user (IF the user has reached TLX)”