I just don't get why Apple doesn't recognize this as a problem. Do the engineers working on macOS all have two of these 5:1 aspect ratio ultra wide monitors!?
But Microsoft managed to deal with that issue - years ago. With XP they introduced collapsible tray area and later, it also become possible to rearrange icons.
Somehow for Apple the problem doesn't exist or they assume that their users will choose a 3rd party solution. Frankly, it's them who should provide the solution straight within the operating system. Especially when Apple computers revolve nowadays more around laptops which by definition have smaller display area.
Especially with the abomination that is The Notch, the menu bar has been overcrowded for years. No offense to OP. I’m talking about the 5 or so items I can’t get rid of in there.