Now I use a 43" 4k monitor and use most of the middle 2/3rds. I would use an extra wide monitor but they're made excessively wide & short. When playing games I can use 2560x1440 @59 Hz and the monitor knows to do 1:1 pixels so it's only using the centre of the display. I'm not so hardcore I need higher refresh rates--though the buttery smooth scrolling on new Macbooks is nice.
I generally do all my work on one screen and keep email / teams / Spotify on the laptop screen.
ADHD means "out of sight out of mind"
But I used to work with another guy. Also ADHD. And he said he absolutely had to restrict himself to smaller, single screens, in order to focus because looking at multiple windows at once was anathema to his ADHD.
Just doubly reinforces how unique brains are. Even with the same diagnosis, different strategies.
It sucks, because it sure looks fun to do some work in a coffee shop or whatever from time to time!
And not wanting to tell you it is wrong if this works great for you, but tbh I wouldn't see the necessity in this setup for multiple monitors, by your first post had assumed a very different kind of work ;)