it's common on many other cars. and yes manufacturers are figuring out to update/modify their coat process.
if ford replaces for free because you're within the corrosion warranty on the car - good on them - but wheels are oft excluded from corrosion warranties.
if they don't - because wheels - it's a simpler fix. but re polishing wheels other than minor work - isn't hard.
now for the other bit - other than cosmetic - there is nothing structurally wrong with your wheel - and it will not continue to corrode down below that surface. Cast and machined AL alloys don't behave that way. so your wheel will not fail on you because of some minor surface corrosion. deeper corrosion in AL is rare in cast alloys and easily found because it begins to dust or flake off.
so other than cosmetic cleaning - it's not a safety issue - or well - shouldn't be. If you have actual cracking of the wheel - that's a whole other issue.