Special cases in layout are a thing, happens a lot once you start nesting third-party widgets. So yes, there may be enough of a use-case for overriding px-3 that it wouldn't make sense to specifically omit it as a utility class -- to say nothing of it being useful as a utility class to begin with.

I only sprinkle in the very occasional tailwind class via UnoCSS. I don't have the fire in me to dig trenches for either side of this battle that some people want to make all this into.