That's because about 90% of porn games are actually patreon/subscribestar shekel scamming (and many of them are just VNs and RPGM crap). Calling many of the titles in these forums a game is already a huge stretch.
If you want to do some proper comparison, how about comparing this "game" to actual good non-porn indie games released in the past decade, many of which received a lot less funding than this one?
Also, I actually enjoyed this porn game, despite it being much simpler in concept and ripping off the gameplay of a popular non-porn indie game:
https://f95zone.to/threads/last-evil-v3-0-1-flametorch.47693/
But for the most part, porn games are trash and the sex scenes will never match the quality of standalone animations, which ironically, is what this guy was praised for (despite its beastiality niche).
Another tech demo that has been around for a while on UE is Wild Life, which at this point has turned into a 3D sex poser.