Looks like O2 are starting to roll this out, which should help cut out some of the scams we see --Brand ID and Call Defence: Nuisance calls and texts | Help & Support | O2
Brand ID lets you know when a genuine business is calling by showing their name on your screen, while Call Defence checks phone numbers to let you know if a call might be a scam or spam. It’s up to you whether you answer, but remember you should always be wary when giving any personal information over the phone.