HereForTheBeer: Guess there are a bunch of different ways they could screw with the customer, not just by slowing things down and then allowing you to 'buy back' the speed you're already paying for.
Apparently we are looking at this from completely different directions. I am not talking about the end-user (you and me), what we have to pay for out internet connection. For that, I am fine with the idea that heavy users (those who stream HD or 4K Netflix all the time, or use the gogrepo.py tool to download all their 1414 GOG game installers in one swoop) pay more for their internets than the old granny who uses internet once a month to get a cookie recipe online.
The ISP/telecom company is free to come up different plans for different users, like the granny can have a basic internet connection with a 5GB monthly data cap and pay only $5 months for it, while I, a power user, would have to pay $50/month for unlimited (or a much higher data cap) internet. I'm fine with that idea, I transfer more data, so I pay more for my internet.
The main problem, at least for me, with abolishing net neutrality is that some big US telecom companies get a competitive edge to push their own (or affiliated) streaming services, by either making the competitors' services slower, or more expensive (because the competitors would have to pay for that telecom company so that its customers can get the content at full speed). That is bad for innovation and adoption of new competing online services.
If the telecom companies feel that the end-users are using heavy streaming services too much nowadays (lowering their profit margins), then they just need to come up with correct pricing levels for different types of users, e.g. by using data caps. But those data caps have to apply to all online services evenly, it shouldn't be so that service A is either slower or costs more to me than service B, just because service B is owned by the telecom company.
I've understood that in many parts of US there is not much competition between telecom companies/ISPs, which makes the problem worse. Then the end-user who is not fine with the ISP throttling different services can't just easily switch to another ISP that is not doing it. Here where I live, we fortunately have a very healthy competition between at least three big telecom companies, which is the reason there are not even any data caps in use, even in most basic and cheapest internet connections, including mobile internet.
The flipside of this is that yes people do use their internet connections heavily, which can mean that e.g. in the evenings at least mobile internet connections can be considerably slower (e.g. my LTE 4G mobile internet can be down to like 12Mbps at the busiest time, but in the middle of the night can be around 30-50Mbps at my home (I have clocked faster speeds even at day time elsewhere with the same connection, even over 100Mbps. so the slower speed at my home is also about the signal strength)).