Sometimes you end up in a job with no good transit routes from where you can afford to live, so you have to drive hours a day. Search the web for stories about "supercommuters".
Compared to any of that, a 30 min bike ride is downright lovely.
I've seen this argument before, and I don't understand how working from home changes this honestly.
Why not just start your day with a bike ride for leisure? Unbound by the location of your office you can now cycle to any arbitrary location. If you struggle to do it without a reason, perhaps cycle to a bakery or store and pickup some fresh food for the day.
For me, it's a motivation issue. I had to go to work and had to cycle/walk there. Now, going out in the morning is optional. If I stayed up too late or if the weather is bad (it's almost always bad in Scotland) I'll make an excuse and not go out. After doing it a few times, I broke my morning habit and it's extremely difficult to force myself to go out.
I know it doesn't really make sense but that just adds to frustration. I hate that I cannot force myself to do daily exercise and it makes me feel like shit, creating a sort of feedback loop. I don't go out and do exercise because I feel like shit and I feel more shit because I don't exercise.
There are many comments here about missing their commutes as they could meditate/reflect on things, etc. One can quite easily do this with meditation or walking/running/biking for ~30 mins. However it takes discipline to carve out that 30 mins and leave it specifically for meditation or whatever.