For me, as long as the legs are covered by anything, I'm fine to 0 F. Jeans are too heavy, stiff, friction generating and slow to dry. I just get by with loose fitting dockers, or lightweight cargo pants.

I tried wool pants and then discovered that synthetic fleece pants are just as warm and last far, far longer.

QFT! A quality pair of wool pants are ideal. They cut the wind, shed snow & are fashionable. Long johns underneath on the cold days.

I have lined jeans but don't like them much for cycling. The lining tends to slide around between the jeans and your legs. I roll up my pants instead of straps so with the lining they become excessively bulky.