Check the Bo1 meta from the same site:
https://mtgarena.pro/meta/
Then specifically, at the mono red thing: the 55% global winrate seems unspectacular, your game is most likely done in around 5 minutes, so when your control deck has eked out one win,
the aggro has already produced three, maybe four. If you hit a nice sequence of going first, the opponent being mana screwed, etc., you will up a rank, or get a good event run.
If you want higher numbers, you need skill and meta knowledge. And of course a bit of luck. Sometimes you will lose to a shit deck because of mana screw, or they draw exactly the right shit
to ride the tempo train.
But the top decks on that list should all be strong enough for your needs. The rest is up to you reading the meta and tweaking them (or abandon a deck and pick another one).
If you're specifically looking for a deck that's good for Standard Event, start noting what you're being paired against. First three games are a crapshoot - you can get people with starter decks, budget builts, wacky shit,
but on fourth win and beyond, you'll start seeing the meta top dogs - these are the decks to beat, so you should either play one of those (and know how it ticks so you can pick it apart in the mirror game),
or get a deck with good matchup against those.
So should we take bets on which card(s) will be banned? Will it be just Oko, or will Oko be joined by OUaT, Goose and/or Veil?
I think Oko for sure, and 60% chance for Once Upon a Time to be OUT.
I saw somewhere that 6/8 of the Top8 at the recent Mythic championshit is different permutations of the same Oko/Goose/Wolf/Nissa ramp engine. If WotC was waiting for a wake up call, I think something dominating 75% of the top meta
would be it, cause if this shit isn't meta warping, I don't know what is.
Once Upon a Time doesn't strike me as a problem card. It tends to fix the first turn quite nicely for a lot of decks (UG Flash, Adventures, GR), but the second and third copy is nowhere near as welcome.
Of course, it's a logical and automatic 4x in pretty much any green deck out there, but it's more of a consistency boost similar to Opt rather than something problematic.