No, it's not relative. "This game has been optimized for the explicit purpose of "engagement"/addiction"" is a statement that can be factually known to be true or false.

> but come one, it's free-to-play. Of course it's trying to keep people hooked.

That's an appeal to emotion without a logical argument behind it. The logical argument is that the survival of free-to-play games depends on the microtransaction revenue being higher than the cost to run the game. You know what directly contributes to the cost of running the game? People using the servers. Unlike social media platforms that monetize through time spent = ad impressions, free-to-play games do not want to maximize the amount of time spent playing the game, they want to maximize the amount of cosmetics that people buy, which is very different, and is not obviously connected with playtime in any research I'm aware of.

> I also know multiple people who had to cope with Dota addictions ruining their relationships and lives

...which happened to me! But, as someone who is struggling with an HN addicition: something can be addicting without being purposefully designed to be that way - addictive traits do not imply that something was designed to be addictive.