That comment is making a deduction given the details of the business, and includes the commenters thoughts about it's future. WRT merely, when saying "they are merely adding a middle-man to probation", that's not reductionism if they're indeed "merely adding a middle-man to probation". WRT your citation of the guidelines, this interpretation might indeed be the strongest plausible interpretation of this business model that the founders have been explaining.

If I wrote yet another minimal lisp implementation in a weekend, and marketed it as if it was going to best Chez Scheme in all benchmarks, and someone came along and told "yeah but this is just a reiteration of sth. we already had, nothing new here, and your ways seem a bit shady", would we have to discount it as reductionism?

You might disagree what people think, but you should not think and decide instead of them. I appreciate the work you do as a moderator of this fabulous community, but in this case you're openly siding with one side of the discourse. Either do not do that, or add to the guidelines that "HN moderation will vouch for what HN companies are doing, disagreements on their busines models are unwelcome". And also, while at it, I can not vouch for the comment I'm talking about, and I would rather.