Does anybody else feel like this? Is this the real reason we all want to FIRE? Do you ever stop and contemplate what it would be like to gain those 8+ hours a day back?
Yes, I constantly feel like this. If I could do what I do for 3-4 hours a day instead of 8, I'd be actually
happy with employment. I'm not happy doing ANYTHING for eight hours a day -- watching movies, exercising, socializing, it doesn't matter. It's too many hours devoted to essentially the same thing, day after day.
I think that humans have evolved to work hard for 3-5 hours a day (not even necessarily all at once) and socialize, rest, and play games (e.g. child rearing, leisure activities) for the remainder. 8 plus commute for decades is just ... ugh.
In my experience, employers offer a 1-size fits all schedule for the vast majority of office workers. You can't take half salary to work half of the hours. Once in a while a specific employer might let you get away with 4-day workweeks but even that is rare and some of it depends on what job/industry you're in.
And yes, the employer model has absolutely helped drive me toward FIRE. I simply don't like so many of my hours every day being devoted to work and because part-time positions are so difficult to find/negotiate, I've concluded that it's easier to just hit your number and be done with the office game entirely.
True Anecdotal Backing Story: A very well qualified software engineer was let go from my current employer demanding for 4-day workweeks. (She was ready to accept the corresponding 20% reduction in compensation, no problem). Rather than jump through the administrative hoops required to grant her request, management just let her walk, figuring they could hire someone else.... and they have.