I'm sure there's legitimate, law-abiding users of all of these things that get caught in the crossfire... but if the platforms will not impose a minimal amount of moderation one shouldn't be surprised that others will want to deny them services and business relationships.
Even if not, why is Apple or any other organization obligated to host them?
You lost your wager. Majority of Parler users are not. If you dig enough, you can find shit - just as easy as on Twitter or Facebook, which hosts hundreds of violent groups and thousands of stupid comments which can be interpreted as advocating violence, though in 99.9% of cases it's just people being stupid on the internet - but majority of the users aren't that. It's just regular people who happen to be to the right of Jack Dorsey politically.
You even quoted “either” and cropped off “or”.
Even a completely galaxy brain position on speech that promotes private platforms which must allow completely unmoderated content actively promoting and organizing violence... hanging out with the people doing that is tacit endorsement.
> Participating without challenging that is giving it a veneer of legitimacy
That's bullshit, and moreover, this is asinine and dangerous bullshit. Any idiot can write anything on a public site, and there's no moderation team in the world that can police everything with 100% accuracy. Facebook and Twitter, despite millions spent on moderation, are full of hateful content and host hundreds of violent groups. Twitter used to host Hamas and Hezbollah until 2019. Does it mean every single Twitter user until 2019 were sheltering terrorist groups Hamas and Hezbollah? This is just idiotic. Of course no user can know who else writes what on a large public service, and no user owes to anyone to police the content of large public service. It makes as much sense as demanding me to police the speech of everyone in my city or move out. Only my city has a million people and twitter has hundreds of millions - so it's more like either you police the speech of everyone in your country or you must emigrate. Or you are responsible for everything anybody ever said within your country. As I said, utterly asinine, idiotic and dangerous. I am not talking about specialized forums that are explicitly declared as belonging to particular movement - like Stormfront - I am talking about generic platform that is open to anybody and hosts millions.
> and lending plausible deniability to a platform clearly designed for them.
This is example of circular logic. You declare that Parler is platform for specific kind of bad people, and when you're pointed out that vast majority of the users aren't those people you claim the platform is "clearly designed" for a tiny minority and all the vast majority is just "gives plausible deniability" to them. It's like claiming the whole USA is built to enable the Zodiac Killer, and everything all the people do is just giving him veneer of legitimacy and that's the point of whole USA existing. That's how you are sounding.
> they’re tolerated and implicitly welcome
It is telling that you said "implicitly". That means you have no proof they are, but pretend to read minds of Parler users and administrators. Too bad it is explicitly knows internet telepathy does not work. On Parler, all the speech that does not violate the law is tolerated (even though it is not endorsed, or agreed with, of course). As it should be on every free platform. There is absolutely nothing wrong with that. It's called "free speech", and once it was a value of America. Not anymore, of course.
Where is the data please, instead of wild guesses?
They’re a pre-series A startup with a very small staff. If people don’t report things, it’s not feasible to expect that they’ll all be actioned. Instead of reporting the post, activists with an agenda thought it better to cherry pick them and attack platforms. A more honest test would have been to report the content and see if they acted on it. But let’s not kid ourselves, this campaign was disingenuous from the beginning. The real goal is to shut down a perceived enemy in the culture war.
If it were organized on Telegram would you ban Telegram? If it was organized by phone would you ban phones? This is just silly.
These platforms are at this moment currently being used to mass hype up an increasingly armed and paranoid segment of the population hyped up on years of cult-like propoganda, conspiracy, and dehumanizing of their imagined enemies. It was a stroke of luck they did not take out Congress the other day, I'm sure some will try again.
If you want a clue where this ends up unabated and exploited, I encourage you to look into the 1994 Rwandan genocide.
People organize violence on twitter almost every single day.
There is everything wrong with enabling a platform which actively supports violence.
You could say exactly the same for Twitter (remember the Hunter Biden laptop story? Of no you don't, because it was censored there), or even Google which clearly de-prioritizes search results based on their ideologies.