Putoline wax. It’s a little effort, and not cheap initially, but there’s a reason why people who try it turn into evangelists about it and never go back to normal oils.
Lasts many times longer than absolutely anything else (yes, including squirt, UBS, or anything oil based). It’s not even worth arguing over how long squirt/UBS last (IME about 50 dry miles, which means a century on the road bike is a noisy experience), or solvent based wax/dry lubes, or oil based wet lubes, nothing lasts even a tenth of the time putoline does.
None of it flings off onto the bike.
It’s a wax so dirt doesn’t stick to it. But it doesn’t wash off like even wet lube does under normal wet conditions (it will eventually, but it needs to be biblical rain for mile after mile).
It is more of a faff (but not much if you chuck it in a mini-fryer whilst you wash the rest of the bike) once every couple of months. Considering that means 20+ rides at least between lubeing, it’s less faff overall by far, especially in winter when it will last for weeks/months on end of muddy singlespeed riding.