It just isn't the case that you can't have a Show HN without signups - it's preferable for the friction-to-try be as low as possible but sometimes 'as low as possible' is, in the given context, still a fair bit of friction. Lots of Show HN's are in very early stages and unpolished, some use finicky/newish technologies, etc. If this particular one is too much of a hassle and you bounce off, that's fine but the suggestion the poster is breaking some sort of rule here is inaccurate.
You click "Play now" and you're in the game. That's less friction than most Show HNs. You’re misinterpreting the rules and being overly zealous for no reason.
> HN users get ornery if you make them jump through hoops
Is in them