Is gatekeeper the new buzzword of the day or something? Seriously though, calm down over there a little. Nobody wants to mindlessly gatekeep people out of content. Do you actually think the typical raider thinks 'wow there's just far too many PFs and people raiding today? Recruiting people for my static is way too easy. I sure wish the scene was half this size?'.
However, there is a very real barrier of progression (Keyword, Progression not Entry) that people do need to be able to reach to continue onward once you hit Extremes. DPS checks are a thing, yet the game does a really poor job of explaining anything beyond 'this button does this when you press it'. The value of weapon damage? Substats? Mainstats? The importance of 2 minute burst windows? When should I save CDs vs blowing everything?
IMHO any negatives (which can be instantly ruled out by SE changing absolutely nothing on their existing harassment policies I'll note) are easily counteracted by the benefits that some form of simplistic in game parsing tool could offer.
Right now a lot of players will hop out of a 24 man where pressing a button 10 times a minute is acceptable into an Extreme where it clearly isn't and have no idea why the content is chewing them up and spitting them out. This could be a potential avenue for them to explore to better understand where they are going wrong. I'm still firmly of the opinion that some kind of gold saucer mini game is the better approach to better facilitate this kind of use.