I halfway was going to just drop it, but decided to come back and also explain it for any few that happened to trip across this time capsule of a comment years down the line, but see it on lemmy instead of kbin, and them getting confused about what I implied earlier

on some social media sites where you upvote yourself by default, it's all fine and dandy since that's the default and everyone already has their own - people looking over messages know it all beforehand and everything is upfront

on somewhere like kbin, where you have to go out of your way to do it, it can come off as manipulation to make a message appear to have a greater consensus than it would otherwise have. the next step up, and in definitely-ethically-dubious territory, is having multiple accounts to upvote yourself to boost your message

early upvotes/downvotes makes others that are quickly passing by a message feel more comfortable piling on one way or the other; group psychology is funky like that. it's also a way some bad actors social engineer the system to get what they want seen to be seen, while burying others. I'm not saying you're doing any of that beyond upvoting only yourself, but maybe this all explains a little better on the reasoning about its sketchiness on upvoting yourself on specific social media that don't give a self upvote by default. It's not a god-awful thing to do since a single vote is mostly innocuous, but it also isn't a good look when someone looks into it and spots it