My understanding is that they will pretend it's a wrong number, but then make a joke or talk about some innocuous hobby and try to build up trust over weeks/months to eventually phish or scam you. I forget where I read it (maybe reddit?) but there was a poster who mentioned a personal experience with one such scam, basically a fake romance scam that led to them losing tens of thousands of dollars wiring money to a fake person who pretended to have fallen in love with them over weeks of back and forth texting.
It doesn't have to work on everyone to be profitable, just the once-in-a-while lonely pensioner!
https://consumer.ftc.gov/consumer-alerts/2024/05/why-its-not...
