for olders iphone models - i am on 15 - are they allowing any sort of extensions? that would allow some apps to make use of of to build things like better speec

for olders iphone models - i am on 15 - are they allowing any sort of extensions? that would allow some apps to make use of of to build things like better speech recognition etc.. i was waiting for siri update and bummed it is not supported on 15. when i use my native language (i mostly do it when in carplay) to search songs etc.. it gets it wrong a lot of times. + a more integrated into things like imessages, whatsapp etc..