I'd only agree if the slogan was the only substantial part of the message, with little or no meaningful content framing it, or if it was intended to be incendiary.
I think the post was sufficiently framed, it provided enough of their opinion on a relevant topic that a little slogan like that can easily be glossed over if you don't wanna read it. The post stands sufficiently on its own, it's not some "cancerous" shitpost as you seem to imply. Thinking that it is, or thinking that it's a slippery slope, is overly reactive. Please don't focus on this one negative component and discount all the other stuff - it was just meant to be a simple comfy nicepost about an anime they liked that brought up a topic they support. It was a slogan, said in a context appropriate for the thread, understated and in moderation.
Also blanket approaches >>>/otaku/2294
are the worst attitude to have when you're trying to discuss any media. That was the one I had the most gripe with when I made that post. I'm only really advocating for a lax attitude towards this, something that demands a modicum of moderation from the poster and modicum of tolerance from the read. i.e. take it easy.
I'd say if things are so highly strung that:>grrr no politics at all
is the prevalent opinion, then it's just as shit as all the other boards that vomit politics, just on another vector.