They improved it over time, if you're using a password you can play without level limits in DS3 and Elden Ring. You'll still be nerfed if your level is higher though.
Every mario party game is very RNG-heavy but i think that's by design. It would get borint very quick if the best player would win every time, and the randomness gives a chance for players who suck at minigames (kids and non-gamers) to win.