But...the letter T isn't a mascot. None of those are mascots. They're logos.
I understand the need to lay claim to a place meant for individualized communication, but I'm personally a little annoyed by the insistence of it. I'm not interested in cute squishy mascots. Having a fun animal as the face of anything reminds me of every lame corporation's attempts to look appealing.
I recognize there's little to no way I'm going to win this fight, but it's in the same vein as the continual server-specific nickname suggestions for functionally the same userbase speaking in the same shared forums.
I think we're doing it because we're used to seeing companies do it, a la every one of them you mentioned. A bunch of us probably liked the Snoo, snoo was cute. It makes sense for newly ex-redditors to immediately remake their own snoo that is theirs and theirs alone and way better than the stinky reddit snoo.
Being used to your company of choice having customer friendly anthro mascots and tribalistic nicknames doesn't make it something we need, and that I intended to leave all of that behind when I left isn't helping my bias in this.
Especially where site-wide symbols like the ones you cited are concerned. I don't think I'm going to end up liking anything that's chosen simply because the kbin logo is already kbin, it was here when I got here, and I genuinely think it's really snazzy. Kudos to the designer who took two things I passionately hate — minimalist artwork and the color purple — and combined them into something enjoyable