What is or isn't a business from a legal point of view strongly differs from what you might perceive as a business. I have ads on the page. There are kits being sold from where I get small provisions. I also sometimes do custom solution development. This page and anything OctoPrint related is therefore going to be considered as commercial in nature under German and European law, just as much as e.g. Tom's channel is considered commercial.
As I said already, moving this outside the EU is not going to help here in any way thanks to the GDPR, it's merely going to allow me the choice between what I want to get sued for if this stuff goes through - pest or cholera, what will it be? I live in the EU and in Germany. I have to abide by their laws. And I'm not going to move away from my friends and family just to be able to run an open source project full time. I already risk a whole ton by doing this full time (don't get me started on the muddy waters that is the whole taxation of the various kinds of income associated with running OctoPrint that make up my livelihood and the constant pressure and fear if something out of my control happens, like Patreon going belly up or whatnot).
People who don't live in the EU or have looked at being self-employed in the EU telling me "This should not be a problem" and "Why don't you just move/hand over control to third parties/try to circumvent law in this or that obvious way" is NOT helping here. This is a very real threat, even if you don't want it to be, and I'm not going to risk getting sued into oblivion. If this becomes the law, I will have to abide by it, with all the downsides of that, period. Suggesting to somehow work around or outright break it is a fairly poor suggestion.
The point of this topic is to spread awareness that this is happening. If you want to discuss which union is better than another, please go into that elsewhere. If you want to split hairs with me on whether I would risk getting sued or slammed with cease and desists from lawyers specialized just in that which run rampant here - don't. Just be glad that apparently where you live things are easier for self employed people who happen to run websites.