If I get up at 4am, I'm going to bed at 8pm. So I'm not saving any time, I'm stealing time from my evening to work in the morning. That's what it ultimately comes down to...stealing personal time to spend on working...
I get up at 4am on days I have to go to the office.
Driving an hour to work at 4:30 sucks but it's better than driving 2 hours to work at 6:30.
On Fridays I either have the day off or have to work 4 hours, alternating each week.
I get up at 4am on the working Friday and finish at 8 exactly like this guy suggests because it feels like I have every week being a 3 day weekend.
It is shit cramming a full working week into Mon-Thursday though. My employer implemented the 4 day work week if we wanted. You still have the work the hours though, so it's quite shit.
I know quite a few people just went back to working 5 days to shorten each day.
That's not the same thing at all. You're already getting up at 4am normally on Friday, and you apparently only work 4 and a half days a week. This meme assumes you work 9-5 5 days a week, and advocates that you spend more time outside those hours working.
If I'm getting up at 4am on the weekends it means I'm going to be running on ~3 hrs of sleep. Which is fine because at least I'll get a few hours of quiet before everyone else wakes up. (Also why I stay up til 1am)