On MacOS, closing the last window of an app does not close that app. (To speed up opening a new window later, I assume.)
Motivation
Let's look at 2 common activities:
A) opening a document/file that is currently closed, or creating a new one. For this, I use finder, or I open (if closed) / switch to (if open) the wanted app from spotlight and do the rest there.
B) looking for a document/file that is open in some window. For this, I use CMD+Tabbing, or click on the app in the dock, or switch to the space where I know the document is located.
Because I use CMD+Tabbing exclusively for (B), I don't want to see apps without windows there.
For completeness: if it's easier/possible to hide these "apps without windows" altogether (without closing them), that's even better. With "hiding altogether", I mean:
hide them from command-tab;
hide them from the dock;
don't switch to them when changing space.
When command tabbing, can I have it exclusively show only apps with document windows open?