Sounds like, economically speaking, you are taking over the costs from your employer for providing a usable workspace.
Depending on where you live, and your living situation renting a small office can be really cheap. In my local area I've seen private office rent for as little as $120 per month, but around $200 is more realistic.
But not all types of employment puts the same amount of costs. Those vary widely. And the possibility for the employee to optimize them also varies.
And all the comments up to now are still ignoring the elephant on the room and didn't touch the opportunity cost of having your entire family work on the same geographic area, and the insane housing costs on the few small areas where a family can do that.
My friend was acually depressed by the fact that he had to work from home. At the first opportunity, he ran to the office.
The point is that previously you had a choice over the amount of space you need at home, there are requirements for WFH. i.e. You need a place where you can work effectively.