Guys, you don't seem to understand how G&W's F-air works.
He just pokes you with it since he can just blatantly fullhop it and get away with it easily since it's hard to whiff punish due to it's huge lingering duration and low aerial cooldown, and because most importantly it threatens you while you're standing or of course if you're jumping as well. Peach's F-air isn't a real poke, but a supplementary pressure or punisher that has the added benefit of being safe on block via proper autocanceling. It's a GOOD MOVE, but it's actual applications for DAMAGING PEOPLE with it are much more limited.
Plus, I want more G&W users besides myself to do this, but G&W is actually able to do a Second Jump Renewal after a perfect ledgehop F-air (or he can just opt to land completely laglessly and possibly set up a tic throw by tapping you with the weak hit and then grabbing you). It's honestly not that hard to do, but for some reason Zac and the others don't seem to get how the input works.
That being said, G&W's F-air is easily a much more practical move, and thus better than Peach's F-air. Peach's F-air either has to be comboed into, used in edgeguards, or used for punishing mistakes in order to actually hit. G&W's will just randomly hit you out of nowhere because it's fast, and he can get away with it a lot more than you may expect.
The way I see this matchup, it's not that hard for G&W to approach Peach, since none of her forward options can really directly go toe to toe with G&W's offenses. Offensively she can do some cool stuff if she gets started (minus the fact G&W gets out of traps more easily than she does), but it's harder for her to start up a well spaced approach in the first place since her comfort zone is a zone that G&W covers very well.
If your opponent is not using fullhop F-air more than B-air, they need a quick slap in the face. Yes that's partly a pun. But I'm quite serious. Fullhop F-air is quite frankly too good, and it's very effective in this matchup as well.