nopeI agree with you, for the record. I also don't think that a (hopefully somewhat scientific) investigation into weapon balance is second-guessing, far from it. That's a great initiative, and it will be instructive to see how the 'meta' forms. I'm more just talking about the people who complain that keeping 6s balanced in the face of the stupid weapons is the reason that valve doesn't support comp tf2. Usually they offer no solution, but if they do suggest one it's basically just a blatant attempt to shoehorn another game's system into tf2, eg pick/ban. We all know that won't work, because it's been tested and yet people still keep suggesting it. Comp tf2 is great as it is, and perhaps a better system can be organised, in which case great, go ahead, but in the meantime don't fix what ain't broken, please.
To be honest I think pick/ban was the compromise to let competitive keep the format while potentially getting official support, and an ingenious one at that. Comp players get enough bans to keep the real meta changing stuff out - wrangler, GRU, etc, but it still relates to the wider game and allows Valve to implement something that appeals to everyone and helps their bottom line whilst keeping the 6v6 meta relatively stable as we like it.
In practice it was always going to be less fun for the established community than just controlling the whitelist to control the game mode, so without the obvious payoff of in-game support and a simple system for doing it (i.e. no plugin or anything) it just seems like a pointless barrier that doesn't change much. But not changing much was part of the point.
If Valve really want the ban data to identify and make changes to unpopular weapons it still might be part of whatever is coming, if and when it does come.