There have been historic instances of corps going against the spirit if not the rule of net neutrality if we have ever really had such a thing in the US

The most open move I recall was made by cell carriers that also owned media companies -AT&T? They would use their cell service to punish or hinder usage of non-owned media. They'd limit the resolution of or throttle the speed of competitors services to their customers. Ex. watch our content at 1080p, but competitors are limited to 480p. That or they would "zero-rate" (not count usage against your data limit) their own services. Ex. watching our content doesn't count against you 1GB limit, but watching our competition's does.

I don't know if it still happens though. I'd be surprised if it wasn't just more subtle now.

I hate the culture of downvoting for simple questions that might seem obvious. If you're lurking and reading this, stop doing that.

My understanding is that no ISP makes it public that they block a large number of sites despite the fact that they are currently technically allowed to do so, but there are a number of isolated incidents of small and short-term access issues that may charitably be mistakes, and also throttling on a site-by-site basis does definitely exist and is employed by a number of ISPs. This regulation does more preventing a backslide into corporate rule and less uplifting our current conditions.

I haven't personally noticed a single thing.