This is very incorrect. +EV is +EV is +EV. The one point that you hinge on that's correct is that a push could be +EV on a specific hand but then widen calling ranges on later hands, which would lessen your ability to push. However, as most correct bubble pushes are very blatantly +EV, given that you're not playing against a complete maniac, you're unlikely to run into a situation in which one close bubble decision closely follows another. Thus, slighty widening your opponents' calling ranges is probably a small enough factor to ignore.

Again, arguments that say that +EV plays are incorrect are inherently wrong by definition of EV, with the notable but hopefully atopical exception of gambler's ruin. Don't play above your bankroll, and squeeze as much EV out of your play as possible.