I think this is one of many un-features in Linux world where
- It would benefit a beginner
- It sounds simple but actually quite complicated to get right (especially if you aim to keep compatibility with things)
- Anyone possessing the skills to implement it neither needs it nor cares about it
As such, for you individually, I suggest just getting more comfortable with tmux (or zellij) and vi-like keybinds for text manipulation. Once you learn those (and set your readline mode to vi), you won't look back. Oh, also, try Ctrl+x Ctrl+e in bash, it might help.
Or switch to emacs and using it as a terminal emulator. In that case you will have to learn and use emacs keybindings, but the selection semantics in the "terminal" will be the same as in the "editor".