You're making a false choice.
Those family members already have POTS service. Some do not need Internet, but all would like it.
Where they live, cellular is NOT an option. No Internet service exists (not even slow and rickety DSL) that they can use for VoIP, as Satellite-based Internet has too high of a RTT to work.
The phone companies want to take away their POTS service.
I'm fine with that, as long as they have something that is at least the same cost & functionality running over VoIP.
Again, MANDATE LTE coverage without limits (my grandma can talk as long as she wants over POTS on a local call with no extra fees), OR, mandate fiber be put in to replace the POTS infrastructure.
Universal service is a something we have had for a long time and depend on. Your food is grown by people that use this.
If that means we have to charge a USF for everyone's Internet, fine with me. If that means we quit spending USF money for things that are not related to providing Universal internet access, also fine (there is a lot of waste there).
What isn't fine is removing an infrastructure that everyone that has ever had a phone paid for with USFs, and not putting in a modern replacement. Essentially, that is theft.