There is help with spams showing up recently in the form of requiring all cellular providers implement a new proposal which will provide new restrictions on “ANY” Carrier to not “forward or put thru” bogus/spam calls.
Today “Stir/Shaken” is a recently implemented protocol developed by IEEE which helped stop PBX;public branch exchanges, calls originating on their exchange from being connected to intended said number dialed.
You might notice now the check mark next to number which indicates the number was “verified” and complies with the Stir/shaken protocol.
The current limiting issue with Stir/Shaken is current law doesn’t require “ANY” calls not originated on their exchange; meaning from another exchange branch, to be dropped and not completed. ‘Only the carrier’ that originates the call going out.
Now there is a revised version which would require “ALL exchange carriers” regardless where it originates from to not forward call.
All telephony companies will be required to enforce this law and it slated to be implemented by mid 2023. This should help a lot on spam calls.
Till then the best free service is included on your iPhone, by deleting, blocking future spam calls from that number and reporting to carrier.