That’s… literally pay to win? Paying real money to skip a grind is the definition of pay to win.

We seem to have different definitions of "win". I consider winning to be the victory screen at the end of a game, not owning things in the game.

I don’t have to be a LOL pro to know that not every champion is balanced equally

They're not, and it doesn't matter. The matchmaking makes a much bigger difference than how well everything is balanced until you're at the top. I've played lanes with bad matchups where I've stomped. I've played in good matchups where I've gotten stomped. Played the same champions on patches where win rates were low and when they were high, and it was the same deal. You can even see this when you watch pro players smurfing in low diamond. They play the most ridiculous builds and still win. The balancing makes so little difference for nearly all players.

There’s a certain irony to your earlier statement about players not wanting to pay for a game “they don’t know they’ll enjoy”, and then in the very next paragraph advocate for a format where players have to either grind countless hours in game or pay real money for each new champion.

If you don't enjoy the game, why would you be grinding any hours or paying anything for new champions?