The fact that someone even asks this question tells me there is something deeply wrong with you he culture these days. No shade on you OP, I’m sure you are a good person. But it’s obvious that corporate propaganda has worked extremely well.

No, absolutely not, you are well within your rights to buy off brand and second hand equipment. Heck, I consider it a moral victory in avoiding the hellish markups the big brands put on their consumables.

Push back when kind of question comes up, we have to counter the propaganda, otherwise it will soon become law. I’m certain home tool manufacturers would move to a printer ink model in a heartbeat. It’s bad enough that there isn’t a universal battery mount as it is.