And yeah, before anyone comes around and goes "But i installed lots of NSP files, went online and I am still not banned": That's annecdotal. Just because you haven't been banned (yet) doesn't mean you haven't been detected or flagged by Nintendo.
But I've been doing it for 3+ months. Unless, by "online" you mean an active connection during gameplay. I launched a game (or two?) with an active connection but I turned on airplane mode immediately after launching. I believe I have done everything that supposedly flags you except for going online with a game and making a custom profile pic with a linked account. I know I will get banned. But I can't believe I'm not yet. After I used NXShop to download (and later redownload using Horizon) around a dozen NSPs I thought I would be banned swiftly. That was close to 3 months ago. Nintendo kinda sucks at this. Pretty much the same story with my friend's console. For now, as long as you don't launch a game while connected, you might be good.