As a 38" ultrawide owner myself, I use vscode or intellij maximized most of the day, depending on the codebase I'm

Browsers only ever get maximized to the left/right half screen for me too

Which is something macos should really improve on though, the ux is pretty bad compared to Windows and Linux there

I split a vs code window and a browser or a browser and terminal window on my 13" mb air. Usually need additional context on the same screen.