Avacyn's not as bad imo. It's a dumb card, but at least it's telegraphed in a LOT of situations.It's not even like Gideon is the stupidest pushed card they've made in White. Avacyn straight up wins on that front because she's just stupidly busted.
Imagine a world where Gideon wasn't just an Elspeth knockoff(or had his ultimate changed to -5 so he wasn't an auto 4 of in any white deck), Avacyn didn't wrath the board when she flips, Emrakul wasn't able to be cheated out on Turn 4/ cast on Turn 8, Spell Queller was Exile Spell CMC 3 or less, Copter had a crew cost of 2 instead of one.
Just like, there's a bunch of little stuff that changed cards from good to pushed.
edit: Realized that Frontier is likely popping up in large part because people hate Standard right now.