Mid-twenties bachelor here, your suspicions are 100% correct. I don't mind WFH
too much, especially now that I have a companion pet, but I definitely feel like I can dig into work with more focus and vigor in the office. It also took a lot of conscious effort on my part to build a healthy hybrid work lifestyle.
For one thing, I don't have the luxury of an entirely separate space to dedicate just to work -- my home office is also my bedroom and personal computer/gaming space.
And as others have noted, its just... way too easy to fall into a pattern where you literally turn into a technological anchorite. I have refused to let myself use food or grocery delivery primarily because I realized there was a point in the depths of 2020 when I hadn't left my apartment in almost two weeks, and it really frightened me how easily the time passed, in a beige blur of life.