A wave of negative Steam reviews—mostly from Chinese players—have hit PlayerUnknown's Battlegrounds in recent days, due to the appearance of an in-game ad in the lobby of PUBG's Chinese servers.
The negative reviews (which you can see for yourself here) are in protest of an in-game ad for a Chinese VPN service that, according to the reviews, appeared in the lobby screen on their games. No other region has reported finding ads in the PUBG lobby.
Coincidentally, Chinese players have previously reported about lag in their servers, even through major data centers in Beijing. As a result, a lot of Chinese players choose to log into other regional servers for a better connection, which has an unintended result of causing lag for players located in those regions.
So the fact that the ad is for a VPN server which advertises a boost in connection to other regional servers feels targeted resulting in widespread complaint from the Chinese player base.
We've reached out to Bluehole to ask whether these in-game ads will soon be populating lobbies in other servers. Considering it costs money to play PUBG, this would seem like a bad move for the company.
Steam recently updated its reviews policies to tackle review bombing by offering histograms that track the reviews of any given game. By most critics accounts however, the new approach to reviews doesn't so much deal with the reviewbomb problem directly as it does just offer more data for players to parse through.