Suing users wasn't enough, actually Valve stepped in when they tried to use legal methods to extract customer information from them. It would have created a precedence of Valve disclosing information for legal reasons, which could have led to them eventually, for any reason, releasing their business data for a legal case. And they are guarding it more than effing Fort Knox. To my knowledge, they did not disclose this information to the Australian courts, despite the judical system demanding to do so, to this day.

Don't they have an entry here already, or from the old GoG part? Asking only because the Arcane Raise series and its developer have been pretty well known for card farming massively and exploiting the DLC system.
(Although, granted, separating basic gameplay elements as DLC is not exactly something he invented, I can barely name an AAA publisher who didn't do it or continues doing it to this day.)

Is it possible to get direct links to those mentioned assets/techdemos? If reporting the games, some direct evidence should be attached for Valve to even pretend they will look at it.
(I am asking because Google just dropped three different things for me for "Cryengine example" and it is a tad difficult to pinpoint which is the one here. I do not mind doing some digging, but I think it is unneeded if someone already uncovered the same thing already. )

Next to its upcoming very money laundering-y 50-dollar no-content DLC and with its notoriously offensive developer that has like half a dozen companies running on Steam to hide his previous "work", I think fake rewards are just the small cherry on top.
But hey, he paid the 100-dollar Direct fee, so Valve is okay with it. As long as we somehow cannot make this go public enough. Apparently, a Jim Sterling video was not enough.

I would drop in another thing, I saw on a SteamGifts forum: if you look at the curator recommendations page of this game, then you can see that every positive recommendation was made by groups where the game "creator" is the admin.
I wonder if this falls into Valve's fake self-review policy.

It is tethering on the verge of being unethical, but no digital store or marketplace has any kind of clause that would prevent it. It is a shameless self-marketing ploy for all those various venues, like you said.

While we could say that people whore out themselves much worse ever since television was invented—and many of us could name at least a dozen internet personalities beyond PewDiePie who self-promote even more shamelessly like this dev—I can agree that it is not something that should be a trend.

On the other hand, this is exactly the type of gimmick you cannot really do many times; after all, people won't get more than one personalised achievement; or, if they do, they could just stick to the one game that gave it to them in the first place.
So, in a sense, it was rather clever, finding an opportunity that may not be exploited ever again and pulling it off in a manner that left most customers satisfied instead of feeling ripped off.

If it really would have been a buy-yourself-an-achievement fraud like the Social Interaction Simulator debacle… now, that is an entirely different can of worms.

Not exactly, any owner is free to ask for a personal achievement:
https://steamhost.cn/steamcommunity_com/app/440730/discussions/0/133257636764514257/
Sponsor in this case means they bought the game.
So, it is more like a marketing ploy to make people who really, REALLY love to customise their profile page to get special personal achievements by buying the game. Since most of them are big-time collectors, I guess they think they would have done it anyway.

Like in pretty much all hentai VNs which are on Steam. Many of them offer the uncensor/eroge patch right in their community page, often from the publisher. This is pretty normal for Steam: the game complies with their needlessly prudish rules, but offers a way for the customers to get the original version easily.

And if you add more, it just overwrites the last one ad infinitum, yes. I just took the time over the past two years and added as many to the filter list manually as I could.

Similar to the paid bot reviews, it is just an extension. This is the reason groups like The Reviewer's Guild are invite-only, because it takes effort to find someone on Steam who is not a meme or a paid reviewer.