> will just confuse users. “Why can’t I type text here??” It’s often better to allow mistakes but also offer immediate explanatory feedback if something is incorrect.
No, it's better to prevent a mistake and offer immediate explanatory feedback why something is incorrect. For example, the answer to "why can't I type text here??" would be a message explaining that no text is allowed, only numbers.
Yes, and make your now useless alpha keys into a perfectly usable numpad so you don't have to use the worse horizontal numbers row or shift your hand to the actual numpad!
No, it's better to prevent a mistake and offer immediate explanatory feedback why something is incorrect. For example, the answer to "why can't I type text here??" would be a message explaining that no text is allowed, only numbers.