With the right gear, cycling in winter isn’t bad at all, provided the path is clear.
Although what a lot of winter bike commuters do in my city is go by bike 95% of the winter, and take the bus when the conditions are really bad.
Always on regular 23c or 25c road tires.
I usually fell over about once per winter, which always kind of sucked. But by my estimation, riding the subway was a more miserable kind of experience.
You slide around a bit but you get used to it. The bike is usually but not always more stable than it feels.