Bit of a straw man, but I imagine products that need 24/7 support would have more than a single owner and would be doing some sort of code review, thus it's not

Bit of a straw man, but I imagine products that need 24/7 support would have more than a single owner and would be doing some sort of code review, thus it's not about you being on-call for eternity, just that you should be involved in the process of supporting code so that you write code that is supportable.