In my opinion whoever thinks that Splinterlands would be more successful on other chains is just a gamer and does not know Hive and its many utilities at all!
Was that the fault of the players for not trying to understand Hive or Splinterlands for not putting more effort explaining it? While players should put the effort to learn about Hive, it is also in the interest of Splinterlands to make it easier for its players to learn about Hive including its social aspects. A simple newbie post link in Discord can do or could just be taken among the previous post that other creators did in the past.
Also while I agree that Splinterlands has put a lot of value to Hive, I think that the Splinterlands contest are a failed opportunity to market Hive since most participants did not add #Hive tag when they post it on social media. Should not be hard to add as a requirement.