That’s what the person was getting at. Does it matter if it can be cross-compiled elsewhere?

It matters to Theo, due to policies created for specific objectives. It does not matter to many other people.

I guess at the end of the day this is all that really matters. If there are specific goals that Theo has around this, then there's no point in me second-guessing whether those are "reasonable"; it's a matter of values and preferences and whatever.

Whereas if this conversation was about something with broader stewardship, like _Linux_, I'd be saying this is silly, you shouldn't be compromising other things just so you can build your RPi kernel on an RPi.