Uh, Lemmy isn’t really big on memes (except over at c/Risa on startrek.website — their Star Trek meme game is on point!), so the old memes are partly satire for those of us that are older than memes and mostly make fun of them. With old memes. It’s complicated.
Just because Chekov wasn’t on the bridge and we didn’t see him doesn’t mean that he wasn’t still part of the crew somewhere else on the ship. When we finally did see Chekov in Season 2, he at no point claimed to have just joined the crew.