Steam policy

The bug they're referring to is related to the "More Like This" section at the bottom of the store page (where similar products are shown). In early October there was indeed a bug which caused the list to show very popular games only. For example, the More Like This section on the Rising World page suddenly showed "similar" games like CS:GO, Assassins Creed, GTA V etc.

This is what Valve wrote about that:
"This change had the unintended side-effect of de-boosting tags in the “More Like This” section on a game's store page. What that meant was that instead of seeing products similar to the game, you saw games that shared just one tag in common, but were effectively the most popular games on Steam"

This issue was indeed fixed very soon, and traffic from the "More Like This" section recovered (mid October).

However, traffic from other sources (in our case, the traffic mainly came from the Steam Home Page [Main Cluster at the top] and Discovery Queue in the past) also dropped significantly in early October, but never recovered. I can't share numbers due to the NDA we signed, but when comparing the numbers from yesterday (Dec 12) with the numbers three months ago (Wednesday, Sep 12), we got 99.4 % less traffic from Discovery Queue and 100% less traffic from Home Page (actually we got 0 visits from Home Page, while it was previously one of our main traffic sources).

We sent two tickets to Valve explaining the situation, but unfortunately we didn't get a proper response. A few days after the issue was covered by the press, Valve posted an official announcement addressing the issue with the "More Like This" section (that's where the quote above comes from), although the "More Like This" section bug wasn't an issue at all, almost every dev who was affected by this issue (there is a huge topic about that in the internal Steamworks forums with almost 900 posts) lost his traffic from the Home Page and/or Discovery Queue.

It looks like the Discovery Queue and Home Page still suffer from the issue that was mentioned by Valve regarding the More Like This section: single tags get too much weighting. Since there are a few very common tags out there which are used by almost every game (e.g. "Singleplayer", "Multiplayer", "Early Access" etc), this seems to drive the traffic towards the very popular games. This explains why something like this happens now (from the r/gamedev post): https://i.redd.it/mrwxdzg901021.png

I don't know if Valve really isn't aware of this issue, although that's very unlikely. PC Gamer covered the response from Valve, but also mentioned that the response is contrary to what other devs reported.

Nevertheless, I will wait a few more weeks to see what happens. We have a Plan B in case the traffic does not recover. If the traffic does not recover until January (or February), we will post an announcement regarding this issue, sharing more data about it, and also reveal our "Plan B"

Thanks for the update. This is actually the first time I see that Valve confirms that they're aware of the issue, or at least that they're aware of the "reports" (and I really hope they're not referring to the "More Like This" section again). Traffic didn't recover in the meantime, but let's wait and see what happens with the traffic in the next weeks