I know you don't agree personally with everything you post, but if you do agree with that sentiment, then perhaps you should voluntarily stop using DDF. I'm pretty sure there are no automated detection tools here for violent or threatening content, nor any hired professional moderators.
Is there a difference from a 1st Amendment standpoint?
DDF has moderators, something Parler does not have.
Not sure what the 1st amendment has to do with any of this, the constitution is a charter that regulates the government, not the people or companies
Lack of moderation allows Apple & Google to remove them which might otherwise be an anti-trust issue.
As Jews we should be the first to ensure violence incitement is not tolerated, and yes we should ask for it to be done on the left as well.