> supporting one single shared clipboard that everything uses properly by defaul

Agree. I got to realize how convenient it is to have one shared clipboard by default after I tried (doom)emacs: behaves like vim, has registers like vim, but default register uses the clipboard. I can still use all the registers as much as I like, but the default one is global and can be shared between apps.

I now configure my vim like this.

I still miss this, however, when working occasionally without a graphical session. Perhaps there's a solution, but I haven't yet bothered to look for it.

It should be included in the :OS section, the tty defaults. From the docs.

"This module configures Emacs for use in the terminal, by providing:

System clipboard integration (through an external clipboard program or OSC-52 escape codes in supported terminals). Cursor-shape changing across evil states (requires a terminal that supports it). Mouse support in the terminal."