Most of the people report different experiences. I like this blog post, it also directly answers who does one need to talk to to get website unblocked:

https://news.ycombinator.com/item?id=47183953

and another one, this was restored in a few hours:

https://news.ycombinator.com/item?id=45538760

Now I am not saying it's a good thing there are so many blocklists, but there are sites who got onto them and then came back. I guess you are required to actually fix stuff, you can't just change nothing in your website and expect to be unblocked.