This is highly contextual. My previous job was hell without extra display. It's bad enough having to shift between : 1. Mainframe DB 2. Web (with 3-4 "apps" open in tabs - including one of our primary tools, various pages to lookup data, mapping system, knowledgebase reference, etc... 3) Terminal Software to log into multiple switching systems (each with their own syntax thus needing the knowledgebase) 4) Teams Chat 5) Mail (neither 4 or 5 these "require" multiple screens and can be shunted down into the taskbar) 6) A chat client (when acting as support/to request support) - Browser based, but kept in a separate window because it is a separate function than just "referring to info/looking info up) Most of this was on one screen but the Browser I always had to keep open on a second screen so I could have it handy to swing to it when needed and not waste minimize/maximize. 7) VOIP software for telephony.

I believe there were other tools (I am no longer at this job, and can't recall them all).

I just know that even on a 1440 screen there was no way working with one monitor would be pleasant. Some people ran multiple DB terminals separately (IBM mainframes); I just switched DBs in the terminal (you could have up to 5 open at a time - but sometimes you'd be working multiple projects and it's easier for some people to just load a second window) If I ran more than one at a time, like others did, that would be yet more complexity.

I can imagine most places only need a few windows open at a time (ultimately that's what you did, because too much info at a time is just as bad as too little) Frankly, I would need a 4k bigass display to really have nicely tiled windows that did everything I needed to without stacking window managers making everything so complex)

The overhead of keeping track of state of all these things and swapping between them quickly was brutal and that's without the actual work done on them. Multi-tasking is a huge pain in the ass.