Matt Bitner, who made A Robot Named Fight, is a one man studio and his game is on Switch, but he ended up teaming with Hitcents for publishing. I don’t know if he tried to self publish first and his game was initially rejected, but his game is also on Steam (was there first) and received a positive reception there, so that undoubtedly helped him get accepted on Switch.
Steam, Android and iOS is where he should go first (I’m aware he had/has issues with iOS). Android is the most open, allowing him to publish very nearly freely. If it’s not compatible with a certain version of Android, no problem; Android just won’t market to that version.
As for my own opinion on why it was rejected: it looks like a Flash game with zero polish and zero effort. Barely any animations, no particle effects, the premise makes absolutely no sense, even with suspension of disbelief; you’re a sentient circular saw blade collecting gold nuts and avoiding spikes, because spikes can somehow damage the blade. He said it’s extremely difficult, but the gameplay videos he showed make it look incredibly easy. It really just looks like something a student whipped up within two weeks for a homework assignment.
There may very well be several one man studios with actual good games getting rejected on Switch, but I believe a part of that is due to garbage devs like RCMADIAX clogging up the Wii U eShop, so Nintendo didn’t want a repeat of that on Switch. Still, as noted, some bad games still manage to slip through. It’s going to happen no matter what.