In the screen that pops up before the op while waiting for players to ready up, they could add an inspect player and vote kick option. Also they could add the harder ops to tier 2 & 3 and lock it until the player has completed the first story modes via group finder a number of times (maybe even giving the player some sort of quest to unlock the harder content in GF).
Those options would be much better than having an auto gear check, allowing guilds some flexibility while making sure people who aren't ready for the content won't be able to play it via group finder.
Just saying "it's too tough" and not finding a solution for the majority to be able to progress onto harder content isn't really right, I'm not paying so some can play the content and I can't even though being fully geared enough for it as I already unsubbed once because of this lack of progression.
The problem is that the engine apparently doesn't allow stuff like that (yet?).