My 27" Samsung display stays connected to my 2015 MacBook Pro (MBP) at all times when I'm home via a standard HDMI cable. The display stays powered on. My MBP sometimes goes to sleep e.g., overnight.
Sometimes, but not every time, the display will fail to connect to the MBP when I wake up the laptop. The display is still on, but the MBP doesn't recognize it—i.e., it acts as if there's no display connected.
Unplugging and re-plugging the HDMI capable into the same MBP HDMI port reestablishes the connection.
I don't recall ever having the same problem with different monitors at work.
This question is similar to some others, but no situation is quite the same.
