While power and property are some of the biggest, control and limiting your free time are the biggest reasons. By forcing you to commute into the office and having near 100% control of you while there, it limits your time and ability to do anything else. This includes looking for other jobs, comparing your salary to market averages, talking with friends, coworkers, or family about jobs and compensation, and interviewing for other jobs.
Working from home gave so much freedom that it made people realize they'd been living in a cage for their entire lives. Need to take a call from a recruiter while WFH? No problem! While in the office? Impossible. Taking interviews or applying for jobs during lunch or breaks is a breeze at home, but you can almost never do so in the office. As most jobs and recruiters will do everything between 9 and 5, that means most jobs by their very nature prevent you from getting another/a better job.
I've lived this myself working remote/hybrid these last two years. I spent a lot of time looking for jobs whenever I was disatisfied and landed a job with better hours, benefits, 100% permanent WFH, promotion, and a 60%+ salary boost just by doing all the things I mentioned above during my free time working from home.
This all tips the scales in the favor of individual workers and labor as a whole. We can have a whole generation who will know their value and leave toxic work environments at the drop of a hat, and that will benefit all workers above and below. It may finally lead to a real “labor shortage” for companies where they'll have to be realistic about requirements for jobs and actually sell themselves to prospective employees.