Ethics aren't different if you're on a 5.12 or a 5.2 ... the only thing different are the egos or lack of humility involved. So yeah, bad on them for leaving it there, no matter who or what.
more people want to climb easier routes. that makes it different, because the chances of someone else's ascent being buggered by gear on a 5.12 at the notoriously-'sandbagged' gunks seems a lot less likely than on a 5.6.
You're still saying that different rules apply to you because you climb 5.12.
It's the symbolism that carries the insult to the huddled masses, not the gear. That's what ethics are about.
I wish you well too, but that doesn't change my mind about the ethics of it.