Your startup idea was to host large amounts of copyrighted material for profit, without checking who had the rights to distribute that material?
In some parts of the EU that's already illegal. Not just a civil tort for which you can be sued, but an actual criminal offence for which you can be prosecuted.
> Your startup idea was to host large amounts of copyrighted material for profit, without checking who had the rights to distribute that material?
of course not don't be silly.
but so far liability was on the uploader, when the police comes knocking you gave out user data and that was it. see, for example, the jsfiddle constant issue with illegal content: https://remysharp.com/2015/09/18/jsbin-toxic-part-5
people miss here that any user generated content could be part of a copyright. even text if they are lyrics. there's NO user platform that's safe.