I think that's a simplistic view, to walk that's 2 hours each side of your day, assuming you are fit enough to walk 30-40 miles a week, do you? Riding 6-7 each way is still a commitment, it's going to be an hour each way with potential change of clothes, maybe having to shower/dry out. My Grandfather tried 8 miles each way in the early 1920's then doing a days work on his feet all day, he managed it for around 6 months & then moved house to be within walking distance of less than a mile, not everybody has that choice.
I'm hoping that all those that have worked from home have found it successful, that their employees have found it has worked, or has found what needs to happen to make it work, then hopefully introduce it as the norm & rotate the staff that needs to come into the office. Hopefully 40-60% of the staff can work at home for any one day & only have to go in 1-2 times a week.