Since high rated players earn 0 points for beating novices, but still lose at least 16 if they take a loss, high rated players are strongly incentivised to leave the game before it starts if they're matched up against someone rated much lower than them, since they have nothing to gain and a lot to lose. This starts at a rating of 2169 against a 1500 rated player.
The reason you earn 0 points is because you're expected to win against that opponent 100% of the time, so you could hypothetically grind your rating up to infinity against much weaker opponents if they gave you points (this is why ratings were inflated last season when you always got at least 1 point for winning). But in reality, there's never truly a 100% chance of winning due to overheating, bugs, and other issues that are beyond your control, which is why players are so strongly incentivised to leave when they have nothing to gain but something to lose.
I don't think there's an ideal solution, but it would probably help a lot to make these games (where the higher rated player can't gain any points) "exhibition" matches, where no points are won or lost by either player regardless of the outcome. This will probably make the higher rated player less likely to quit since they have nothing to lose, and @natejaymusic
pointed out that it will also make experts more likely go easy on novices (since they won't lose any points for losing the game).
What do you guys think?