It turns out that when you mess with people's lives, those people fight back. Stop doxxing people and harassing them if you want business partners to host your forums.
You smother their 'community'. It's a last ditch effort that should be used rarely, but this isn't the first time something like this happened, and it won't be the last.
They might claim that its mere existence psychologically harms marginalized people, but it seems that their real goal is more about power. You get a ton of clout by both appearing as a marginalized person under attack as well as winning victories over enemies. Right now, Keffals and another person are fighting over who gets to take credit for this.
The more long-term goal is to establish a precedent that sites that are "harmful" are simply not allowed to be on the internet. This will serve as an example to any ISP that might consider hosting them or anyone like them in the future. All it will take is someone finding the site, reporting it to Keffals and gang, and the mob flooding their CDNs, data centers, upstreams, and business partners with demands to either deplatform or be deplatformed themselves.
There's currently no defense against the "Layer 8 DDoS".