I may be unusual
But I haven't felt the need for one of these expensive £30+ / month contract deals for many years. Now, when I need a new phone (maybe every 3-5 years) I buy one. Last one cost £400.
I get my Broadband from BT, so get £5/month discount on SIM-only mobile. So I'm paying £5/month for unlimited calls, unlimited texts and 1GB/month data - it was 500MB but it's gone up on renewal. With free access to BT WiFi as well, I've never even needed the full 500MB
But horses for courses I suppose.