Yes, that's part of my point.
Without feats - okay.
Then you add feats. Fighters get to double their damage (roughly speaking). Rogues don't get anything that isn't available to everyone.
The fact remains: there is no feat to make you deadlier in martial combat that doesn't rely on per attack scaling.
An obvious deficiency that make you think the game designers went "the rogue is crazily overpowered in the feat-less game, so we'd better not give it a feat."
But the rogue isn't crazily overpowered in the featless game. Remember cantrip users? They're just as good.
Sure, they can't use feats to improve their abilities either, but unlike rogues that's okay, since they've got so much else going for them. (Plus cantrips are probably too good in featless games)
(In fact, if anything, it's that fighters are offensively weak without feats. Paladins still get their smites. Rogues have their sneak. Cantrips are excellent for Warlocks and Sorcerers.)
But add feats, and the sole loser is the Rogue, that remains frail. If it was a glass cannon, fine, but as a glass pea shooter in feat-enabled games, it's not fine.
At least with my suggestion the Rogue doesn't need to bend over backwards to enable what the game does already provide the potential for, which is dual sneaks per combat round.
It is a feat that doesn't actually add anything, but makes the Rogue class much more relaxed and therefore fun to play