alt Hacker NewsI've been following this issue pretty closely, and it's not only Macs that have this problem with dell monitors, if you check out the dell support forum there are various PC users reporting the problem even dell precision users. Also there are various other problems with the monitor firmware like it crashing and needing to be restarted etc.
Additionally, if you look at the firmware updates they published for the successor U2725QE you'll see things[0] again not specific to Macs like
* resolves monitor wake-from-sleep issues; and * resolves daisy-chained monitors not waking from standby;
Which may not be exactly the same bug, but probably is & it shows the problems are getting addressed in Dell's own firmware
[0]https://www.dell.com/support/home/en-us/drivers/driversdetai...
Unplugging the monitor power for a second solves about half of the issue we're having with our Dell U22DEs, but the plugs are hard to reach so we've seriously considered tripping the relevant power breakers once a week before deciding it was too brutal.
While most users know the power trick by now, there are still those in the "not my job" and "any excuse is a good excuse" categories, and for those I might just spend a little on old fashioned power timers.