>>34461594t. probably one of those three:
Net Neutrality, at its core, is the idea of the fundamental equality of data (in respect to the internet, and the businesses that regulate the connection between the user and the website, and...)
It forbids Internet Service Providers from slowing or even stopping the connection to specific sites over others for any reason, ideological, financial, or otherwise.
If it is legitimately repealed (which, IIRC, it still has to get both Congressional and judicial approval do do so), this would allow ISPs to not only force website owners to pay them money so that their website can maintain traffic, but also charge consumers extra to connect to any given website.
In theory, a perfect competition could regulate this system by itself, but the fact of the matter is that many places have just one or two potential providers, and the current technological and legislative barriers make it very difficult for any additional competitors (even Google Fiber got stonewalled to death in many places) to provide meaningful competition.
This means that there would be virtually nothing stopping ISPs from limiting customers' access to websites in the specific configuration that makes them the most money (including taking bribes from politicians, businesses, etc. to block their competition) beyond a unified protest capable of providing meaningful effect - so either allowing additional competition to proliferate, physically dragging the owners of said ISPs from their homes and lynching them, or... reinstating net neutrality.
Some people say that because it was only instated in 2015, that it would have very little impact on today's market, but even though I'm not an expert on the subject, I gather that the 2015 bill was just placing the internet firmly in the FCC's domain, giving its then-shaky priorities (protecting net neutrality) absolute legitimacy.
As
>>34461663 said, it's a really complex issue, but that's what I understand of it.