People who say "keep politics out of" anything are usually stupid. Most things are political. Implicitly supporting the status quo is political. Leaving things unsaid is political.
Usually the people who pop out that line mean "keep politics that are different than mine out of".
But on topic, punk is extremely political. For example, please review these lyrics from The Clash "Know Your Rights", 1982
You have the right not to be killed
Murder Is a crime!
Unless it was done
By a policeman or an aristocrat
Care to name some media that's about people that has no political dimension?
For example, if a story has only white people or a story has non-white people, that's a political dimension to the story. "Political" doesn't only mean waving a flag.
A story about rescuing a princess from a castle has a political dimension. Super Mario Brothers isn't what most people think of as a "political" game, but that's there. It's saying monarchy is okay, and unremarkably so as it doesn't really spend any time on it. That's not even touching the gender role stuff.
A story about a boy pursuing a girl is rife with political subtext. Why is he pursuing instead of her? Why not an arranged marriage? Why not gay? When does No mean No? All of that stuff is there, whether you like it or not. It might not be noticeable if it's the dominant paradigm, but it's still there.
Someone might say "Well you're just reading into things!". Unfortunately for them, that's like the entirety of literary analysis. Additionally, the author's intent is one tiny sliver of what's important, if it matters at all.
Finding a political dimension in, like, lyric-less chiptune music might be more challenging, but most stuff that involves people has a political aspect to it.
On one hand there probably are a lot of non political things. On the other hand, once you've been involved exclusively into non political things for long enough you may find yourself in a very bad situation politically. Like being governed by arseholes that don't give a damn about you or human rights but everyone thinks that they somehow represent you
Politics (from Ancient Greek πολιτικά (politiká) 'affairs of the cities') is the set of activities that are associated with making decisions in groups, or other forms of power relations among individuals, such as the distribution of resources or status.
That covers literally anything involving a group of people doing things.
Usually the people who pop out that line mean “keep politics that are different than mine out of”.
Really depends imo. A lot of political discourse naturally falls onto the same tracks towards the same repeated talking points, automatically making the worst assumptions about what people mean, being very defensive and suspicious (or even straight hateful) of anyone not proactively signalling being part of the same group. It's important to face it and deal with it but you may want to take muddy boots off before you come in the house.