For example if language has special syntax for numbers people tend to use number as type of account (or string for contact person). Then when software evolves and new information needs to be kept for account and new operations performed the shorthand syntax stands in the way. You can't easily change the type of account from number to complex object without refactoring all of the places in your code where account was used as number. (I'm ignoring languages with overridable operators to make the point).
People tend to obsessively stick to built in stuff (anti-pattern Primitive Obsession) because swapping for what they need now is excessive burden.
What I would very much like to see in languages development is that whenever the syntax gets introduced programmer should be able to use it on more complex things then the syntax was primarily designed for.
If you introduce syntax for operators don't make them work just for few built in types. If you introduce async/await don't make them just work on promises (especially not just built ins) but anything that is shaped like a promise. If you introduce generators make sure that they programmer can implement persistable version of them with the same syntax.