I don't know what that term refers to. Do you have a link?
Discussion
https://en.m.wikipedia.org/wiki/Black_hole_(networking) Sometimes used as a threat against entire ISP if they don’t comply to traffic monitoring standards.
I mentioned that an ISP can censor an ip address in their range. It sounds like black-hole-ing is a form of that. Thankfully, at least right now, it's easy to get around such censorship by renting a different ip address, since there are many ip address providers who do not require identity info. But I imagine it is difficult in some countries to rent an ip address without KYC, and if it becomes difficult worldwide, that will suck pretty badly.
This is correct, but blackholing I am referring to is at a layer above the ISP. If an ISP doesn’t sufficiently comply with an authority, the authority directs name services to prevent access (in and out, that is, black hole) to the range of IP that the ISP controls.