It's common knowledge that Product Hunt is rigged, and they will not heavily punish startups for soliciting upvotes (blatant example: https://twitter.com/minimaxir/status/763156319058616321 ), or even paying for promoted Tweets for their PH submission ( https://twitter.com/minimaxir/status/786286705263251456 ) Relatedly, there is no disclosure when an investor is closely affiliated with a submitted startup (and often…
I'd go so far as to say that all niche markets have non-disclosed "syndicates" of sorts. Life and wealth seminars, professional conferences, information products people, church leaders, podcasts - all promote other people/products/things similar to themselves who also promote them.
It seem more important to understand this and to take it into consideration when looking at something like AngelList or PH. Advocating that these organizations work against the grain of how all niche markets work seems unlikely to be effective.