Neither React nor Solid (if I've understood their types right, had to go looking for that and it's seemingly not in their org? weird) do this so I'm a tad apprehensive as otherwise seems like a pretty obvious DX improvement. Take the following example:

import type { JSX } from 'preact';

// Before
interface MyInputProps extends JSX.InputHTMLAttributes<HTMLInputElement> { ... }

// After
interface MyInputProps extends JSX.InputHTMLAttributes { ... }
interface MyWhackyInputProps extends JSX.InputHTMLAttributes<HTMLButtonElement> { ... }

Users can still supply the generic parameter if they wish but 99% of the time they're going to want the element associated with the attributes which we can simply assume as the default.