If it's raining, you ride or take public transport there. Most employers and commercial centres offer showers for cyclists. If it's too cold, you wear more clothes. Admittedly, most places with good bike use do not have many hills. In cities which have good bike use I see people with trolley-like things attached to the front of their bike - which are useful for kids and also transporting things around. For two people out of town, getting to yours suddenly becomes their problem. Bringing back furniture from ikea is a nonissue as they offer delivery, and the cost of that is still way lower than owning a car. If you want to leave a city you can always rent a car. Getting from A-B faster than a bike will take you is a taxi job, though your mind readjusts.

In cities like copenhagen or amsterdam, bikes have enough mindshare that these concerns are pushed to the back of mind. The fact that you can remain healthy, passively, is a massive bonus; and the lack of cars is stark in comparison to other western countries.

Copenhagen is an extreme case of this; nothing much on the roads except for Teslas, some taxis and buses. Everyone else is on bikes.