I like the landline, it has it`s use`s. I keep mine for incoming calls & emergences only and I don`t get charged. After all, why pay extra for a calls package when I have the mobile.
My BT phone allows callers in my directory to come straight through, but holds all others. The phone will either send unknown numbers to the answerphone or allow them to announce their name & put on hold to see if I want to speak to them. Occasionally, for example, it might be the garage calling me on a number not known to me. I have set the phone to block all International calls. I believe the phone technology can identify known scam calls and simply block them. Timewasters will either hang up or I will ignore them, while automated calls can`t deal with the system.
I have been with BT for many years, with their landline, mobile, broadband, and an extensive TV package. And that's not to say I don`t shop around.
At the end of the contract I always negotiate/haggle and have never failed to get a better deal. Sometimes, even cheaper than the previous contract.