Console user here, sometimes PC user who still has never used a single add-on:

The discourse on Third-Party Tools that screw with the legitimacy of wins and stuff is really bad, but there are lots of add-ons out there that people use that I appreciate the existence of. Things like in-game chat bubbles for player text (TAKE NOTE, SE!), or player fixes for vastly needed things like Viera and Hrothgar hats. The game as a whole benefits from these and SE needs to take note and actually fix things, because players are only doing it themselves because SE is too slow on the draw.

I don't endorse any kind of add-on that unfairly skews gameplay for one's favor, but if you start invasive file checking on the game client and PC files, it's not going to end well for literally anyone involved. This would be a scorched earth approach and should be avoided at all costs.