> That counts against you because now you have even fewer keys to work with to add copy/paste, shouldn't that extra physical key be instead used for those extra useful letters?

Those are not extra physical keys. Some buttons on the left of ENTER has the Å Ä Ö, that's all.

I'm currently on a Swedish TKL keyboard.

See https://typingdonewell.com/blog/what-is-a-nordic-layout-the-...

> Those are not extra physical keys

I know, that's why if you do add extra physical keys, they have to compete with the useful dacritics or the commas that those diacritics replaced, so it's harder to justify using those extra physical keys for copy/paste