What this article is clearly missing is that "hobbies" is a very modern concept. Humans never evolved to engage in semi-serious idle pursuits. We have evolved to compete and seek progress.

What's happening is that the definition of competition and progress has been massively reconfigured due to social media. But even in pre-Industrial days, people worked hard to be better off, to accumulate wealth, to increase their social status. In fact, industrialization is a result of that ingrained work ethic.

Asking people to be OK with mediocrity is like asking warring nations not to go to war. It's a well-intentioned but ultimately stupid advice because it doesn't work. What could work however is reconfiguring social media and environment: the less an individual gets exposed to competence, the more s/he'll be able to enjoy whatever s/he is enjoying.