The idea that an attachment would do one thing to one gun and something completely different on another, seems to me to be designed to cause confusion. Add in the fact that most attachments already do so little that they may as well do nothing at all, and I'm pretty sure you'd end up in a situation where a player would literally have to have a second screen open so they could wiki something before they pick it up, or otherwise have no idea what it would do or what it's supposed to do.
Maybe this is just me being cranky, but I find the current system already has so many flaws that I'm not at all certain I want the devs to rebuild it - probably in an even worse state than what we have now. And all for the purpose of what? Helping day one players be less bored? I'm a day one player and I'll tell you right now that if they want me to be less bored then they can start putting actual high-value loot on the maps again, and stop relying on the trashy bin reset to make people feel better about all the zero-value loot. And fix matchmaking. And skill assessment. And ban cheaters. And ban secondaries. And do LTMs that are fun instead of the same old "die, respawn, die again, respawn again" garbage we keep getting under different names. Just my two cents.