The idea that companies track you based on IP is a fallacy, they use cookies and similar technologies. Even if everyone had static addressing at home and companies like google could guarantee this was the case globally, people still travel so the same device can pop up from multiple different locations with wildly different source addresses. I have multiple devices at home, but on the same VLAN they originate from the same IPv6 /64. Sites like google consider them different users, and even guess completely different physical locations for them which are hundreds of km apart.
Having a shared IP is a hassle, and a frequently rotating one isn't far behind.
Just because you have a unique IP, doesn't mean external companies know who it belongs to unless the ISP informs them.
Allowing them to track you will actually alleviate the anti-bot problems, as they can identify you as a known user. The anti-bot measures kick in when you are a *new* user as far as the system is concerned.
If you are a new user from a new ip then you get some leeway, if you are a new user from a previously seem ip then you look more malicious as bots will never retain cookies as if the bots could be tracked they would be trivially banned, and will always show as multiple users from the same address.
ISPs probably also like it because it means that without extensive logging, for which there is no business justification, they can't identify who downloaded some movie that the MAFIAA et. al. want to sue over.
Depending on your location you will probably find that this extensive logging is mandated by law. And since the logging is being done anyway, the ISP will look for ways to recoup the costs which often involve selling the data.
You think organisations like the MPAA will accept a response of "well it could be any one of 50 different users" and just give up? Absolutely not, they will either go after all 50 users with threats, or go after the ISP etc.
Europol gave a presentation on this:
https://ripe74.ripe.net/presen...
The Europol investigation also highlights a "could be any of 50 users" problem which resulted in 49 innocent people being intrusively investigated for a serious crime committed by someone else. If you're concerned about privacy you absolutely don't want a shared IP because then you're either facing detailed logging or possible intrusive investigation through no fault of your own.