I don't play plinko very often, but in my experience, betting $0.1 and dropping the ball 10 times in a row most often results in a loss of $0.3-$0.8, which means that to reach a $100 wager you have to be willing to lose $3-$8, which I think is bad
I think you missed a zero, as it’s supposed to be $0.03 and $0.08 for the math to add up.

The RTP for the Plinko game on Yeet is 99%. So, if you wager $100, you are supposed to lose about $1. But that’s only in theory. Still, a $3–$5 loss isn’t that bad, imo.
For me, my favorite game to farm wagers is dice. I just place the smallest bet on the best odds and turn on autobet (you need to read the relevant terms first to see if those bets will count toward the total wager).
There's bound to be a bit of variation - sometimes you might win ten in a row. That being said it's worth looking through the fine print because I've often found the games can have different rates or bonuses for each betting amount, not saying it's the case here but it might be 98% RTP at 0.1 and 99% at 1. Either way it would be interesting to see evidence on this because unless you have a large sample size to show it is just the usual swings you can find in any casino game.