In my experience, these decisions are usually made by product or design people.

The one that annoys me most is whenever someone needs to enter a code with a fixed length. Like a 6 digit OTP code. They want to have a UI with 6 separate input fields: _ _ _ _ _ _ that behaves like one input and only allows the correct values and has the cursor behave correctly jumping from one box to the next as you type / backspace. Turns out, creating that UI element is kinda time consuming and adds NOTHING and at best results in the same user experience as just tossing in an HTML input element, and more often than not results in some non-standard behavior that breaks something (auto-fill, paste, arrow key, accessibility, etc, etc). Just use a standard input, throw some css on it to make it the characters big if you want.