Dual displays slow to start after installing Sequoia - Solved

I installed a new Mac Studio about 2 years ago to replace my old cheese grater Mac pro, including dual24" (1920x1080) monitors. Everything worked fine until a few weeks ago, when I finally bit the bullet and did the first OS update (to OS 15.5) on the new Mac. I worked through the usual kinds of bugs, but I Just could not solve one: slow recognition of my monitors.

Typically the Mac would start up with just one monitor displaying everything that had been displayed across the 2 screens. The second monitor would be black with a faint flicker every 5 seconds or so. Then after maybe a minute or so, the second monitor would light up, all the open windows would snap into their old positions across the two screens, and everything would work normally until the next time the Mac went to sleep.

Clearly not a disaster, but a giant PITA, especially after everything had worked so well. Lots of time searching the various forums educated me on a whole bunch of really terrible display problems, but nothing like mine (and I had no interest in exploring the more radical possible solutions, since, as I said, everything worked fine after a delay of a minute or two.

SOLUTION FOUND: As I sat looking at System Settings/Displays waiting for inspiration, I noticed something: The checked display setting was the top one "1920x1200 (Default)" I'd never thought much about that, because it was the setting that had been working perfectly under the older OS version.. Just for grins, I tried checking the setting below "1920x 1080" and restarted.

PROBLEM SOLVED!!!

The weird thing is that the native resolution of these monitors is, in fact, listed as 1920x1200, So I think the problem may have had to do with the newer OS being unhappy with a "default" setting vs. a manually selected one? Maybe some day in my spare time I'll experiment some more.