A hard fork is inevitable once enough people update to core 30. The blockchain without childporn will retain the title of Bitcoin.
This entire scenario has already played out before.
Nobody wants to run a node full of spam, it costs more money to run.
And when that spam includes child abuse material obviously no one wants to go to prison for hosting that.
Core 30 will destroy themselves.
You don't even have to run knots, just refuse to update if you're running core already

