It's frankly scary that this line of thinking has become so in vogue. Let's exacerbate the definition of something to the point that it must be censored.
Example:
"takes a disproportionate amount of effort to refute"
-> This is a pretty decent definition of toxicity
-> Silencing it is really the only effective way to deal with it.
Once you've admitted it's toxic, and not just a dissenting opinion, the alternative is to allow the quality of discussion to fall until it arrives at the unmoderated mean, where no intellectual or valuable conversation occurs. There are infinite places online to engage at that level.
Edit: I'm not asserting that this particular case is in fact toxic. Anyway, it's subjective.
I'm understand. I'm generally in favor of people being able to express controversial opinions held in good faith. But I've been forced to accept that some people just need to be shut up however possible. In this case I'm not saying he should have his blog taken away, but I am saying no one should amplify content like this.
In the abstract, something is toxic if it disrupts or makes impossible desired processes even in very small amounts. Trolling is obvious, conspiracy theories are closer. Some things inherently generate more heat than light, suck oxygen out of productive conversation. You don't have to be a radical leftist (I'm really not at all), you can just watch it happen here or any other forum.
Example:
"takes a disproportionate amount of effort to refute" -> This is a pretty decent definition of toxicity -> Silencing it is really the only effective way to deal with it.