So, I happen to know the guy who placed 1st (Chris Avellino) in the Sportsman category at the 2022 Tucson Aerobatic Shootout; he flies an AJ Aircraft 91" Raven for pattern flight. His caller for that event, Dave Ellis, won a number of IMAC events in the Southwest region as well in the Novice category, and was flying an Extreme Flight 70" Extra 300. For pattern flying, there may be other planes out there, but from what I've seen the majority of wins happening with (at least in the Southwest region) they've been with Extras or Edges.
Now, do you need to go with one of those types of planes? No. You can certainly fly others, and many have and many do.
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Foamboard planes, however, I wouldn't put any of them up in competition against some of the bigger planes. They don't have the mass that the bigger planes do, and in all honesty, that mass makes a big difference in the precision flying, since it's not quite as twitchy or affected by wind as a smaller/lighter plane.
If you're just wanting to practice basic maneuvers, sure, a foamboard plane will let you get the concept down, but if you're going to be doing serious competition, I think you'll want something bigger with more mass.