How soon will the first stable version of SDL3 be released?

The best answer is this list right here:

(It’s called “3.2.0” because that will be the first official release of SDL3–the version in revision control is already 3.0.0, so 3.2.0 keeps us on an even number release version and demonstrates people aren’t on prerelease versions that could be months out of date if they have a “3.0.0” version.)

That list gets added to, and sometimes we close things on that list as “we thought about this and decided not to,” so it’s not a fixed number decrementing towards zero, but it should give you an idea of where we are day to day.