When I want to type a special non-English character like Ø, on my Android phone I simply long press on “o” on the keyboard and it brings up every variation of the letter o you could think of.
On Windows, the best you get is “please memorise this giant list of four number codes”. If I’m going to have to google the code I’m probably just going to copy the letter and paste it into whatever I’m writing.
Why not add them to the damn emoji menu (Windows key + .)
It can be configured that way. But by default macOS behaves like Android/iOS keyboard. Personally, I’ve never had to long press to repeatedly type a key. Why is that a useful feature?