That is entirely ISP dependent and many don't actually work like that. Your cable modem gets a specific IP for as long as Comcast or whoever sees fit, restarting does nothing on the WAN side.

It depends on the DHCP part and your provider lease time. When you access the Internet through a modem and landline, it's an highly dynamical system, where it's difficult to guarantee every caller/user gets its own IP. Especially when IP sharing is used among the clients. Even more difficult it is with the mobile Internet. It's a constant connection loosing/reconnecting. Actually resetting and freeing up IPs for new devices, the whole time. With cable Internet (the TV cable) one is having a kind of stationary access point. The network provider can see it's topology and it never changes once a leafe has joined the network. I typically have the same access creds over months. Even when I restart my cable modem, it's still the same IP. When I was on modem, I could get a new IP every second of I wanted. Now I have to think twice, because I just can't get a new IP, even if is forcedly, not.

Doesn't work like that, only on mobile phones you can toggle airplane mode to get a new ip assigned and cgnat makes sure mobile ips are "trusted" , but they fingerprint you beyond ip address