I’ve gotten prepaid sims for things but obviously that’s not really a feasible method for your main life phone.
i’ve been using prepaid sims for over a decade and a half now and it works okay for me since i only use a voip number that forwards to my phones.
every major carrier i’ve used in the united states have required some sort of identifying information like a state issued id or credit card; maybe the smaller/re-sale carriers will let you use cash.