Argument from fallacy is the formal fallacy of analyzing an argument and inferring that, since it contains a fallacy, its conclusion must be false.

Where is the claim of a false conclusion? You're just proving you don't understand the fallacy.

considering we are discussing the host of the information being the proverbial nazi bar

Source: Nazi bar

The irrelevance & irrationality of the objection to the credibility of the graph is being ridiculed.

It's basically

I don't like that source, because with a few degrees of separation irrelevant to the truth of anything I can relate something else to Nazis.

Pretty much anything can relate irrelevantly to Nazis: they express ideas in the same language, use the same internet, breathe the same air.

By that logic, we should reject sources in any language, online system, or atmosphere Nazis have touched. Where are those objections? Why are you using Nazi-tainted language, internet, and air?

Where are the objections to the credibility of tweets often reposted here?

By arguing against open media usable by anyone because villains have posted some articles we need to take effort to locate & read, they're basically claiming we need to be babied & nannied by having content we dislike excluded for us, because we can't be expected to do that ourselves. The expectation is patronizing.

If the concern is ad revenue, substack doesn't work that way: revenue is subscription-based on commission fees charged to writers. No one gets revenue from free articles: if anything, freeloaders cost substack bandwidth.