I get very few of these
calls/Text and I put it down to registering my phone numbers with the free TPS (Telephone Preference Service),
You can also change your Phone call/Text preferences here,
You can block most calls on Android using this information,
and there are plenty on the Playstore for Android and on the Apple store.
I use,"Should I Answer" which has a large database of bad numbers and no ads unlike other Number Blockers,