Re random IPs,
Sure, but my point is there is no such thing as a “truly random” IP address. You receive an IP from your ISP or VPN provider, that provider has a pool of IP addresses. Dynamic means you get one from the pool. Static means you get the one reserved for you, from a similar pool. The security/privacy benefits are nearly zero and not worth highlighting as an advantage.
Re static IP,
https://nordvpn.com/blog/static-ip-vs-dynamic-ip-address/ says,
Costly. Static addresses usually cost more for ISPs and consumers than dynamic IP addresses.
Except now they know the individuals using your Internet.
Sure if you live alone they already can easily put that information together. However if you have a partner, a relative and children all living in one house they now know who is in that home.
Plus maybe no one in the house uses Twitter and Aunt Alice the Twitter user came to visit, does she need to reverify? Your ISP knows that now.
ISPs would be gaining a lot of new information.