The single biggest reason that unicycling isn’t more popular isn’t that it’s “hard” - getting good at anything is hard - it’s that you can’t do anything at first.
Tennis is hard, but you can buy a racquet and a can of balls and have fun playing a reasonable simulation of the game within minutes. Playing piano is hard, but a total novice can sit down and plink out a tune. Ditto the huge majority of sports and activities people do. Not unicycling. Most people who buy one never get to the very basic level of being able to get on it and ride around, and they quit. And that sucks.
I don’t think getting good at unicycling is harder than getting good at tennis, or piano, or anything else - it’s just that getting started bit that’s different - and if this thing really made it easier to get started, it would be great. It wouldn’t make the rest of your unicycling progress any less of a satisfying accomplishment, it would just get to to where you could make an honest choice about whether the sport is for you or not.
I guess I’m still skeptical that it would really be any easier to ride than riding a standard unicycle standing up, but if it does, hooray! There’s nothing good about those first baby steps being so hard.