This argument is iffy because it seems to also equally well apply to being down 8 in the first quarter yet no one would go for 2 in that scenario.
And when they do, they will be able to capitalize on the information gained from your 2 point attempt.
In terms of expected value, 2 point conversion attempts are roughly par with extra points, though with so few scoring events in the game you would expect large variance.
So outside of scenarios where it is pure upside (1 point doesn't matter without many more scoring events) teams will opt for the lower variance outcome. This matches practice pretty well IME.
If Baltimore special teams doesn't let a punt return TD happen, Houston had one FG to their name... the entire game.
I don't expect a team will always score, absolutely not a team playing against one of the best defenses in football history. So, I respectfully disagree with your thesis. :)
I also suspect that the probability of converting for 2 goes down with each subsequent attempt. You can expect teams to have a few plays installed specifically for critical 2PC attempts, and you may not want to burn those plays for marginal gain early in the game.