I've played a lot of Dominion with people who have played thousands of games. I've even beat them with some frequency (it's not that hard!).

I don't think Dominion is a good game. It's good if you maybe think cubing is good. And it can be a lot of fun!

But as a game? It's not good. If you have no idea what you are doing and are totally unfamiliar, you can even win pretty easily with some luck. But you won't understand why you won, or rather why others lost.

There are many, many games where everyone can read the rules together and be, more or less, on even footing. Dominion can sometimes be that way, but it can pretty easily be extremely opposite of that.

Or another way of saying it, when the default no-thinking baseline strategy can win frequently enough by chance that it becomes difficult to learn from a single game. In this case, just 'buy silver, then gold, then provinces) can win too often just by chance.