ios 18 on iphone 7 is possible! (read desc)

why no one is porting ios 18 or 17 on iphone 7? what's stopping them?

it looks like an dumb question but trust me! why cant anyone port ios 18 or 17 to iphone 7? because the Soc is A10 Fusion and ipads 6 and 7 (not a joke btw) supported these ios versions and they backported ipad os 18 on ipad 6 pro