"Programmer's best friend" is precisely the wrong thing to do though (it says nothing and only makes the reader confused. Are we talking about a language or a pet? I'm not looking for a friend.). They took a step back with that.
For reference this is the old one, which is much better: https://www.ruby-lang.org/images/about/screenshot-ruby-lang-... From: https://www.ruby-lang.org/en/about/website/
The old one was better because it said something about what the language is and how it benefits the user. "Best friend" is not descriptive. "dynamic language with minimal syntax that is easy to read and write" at least tells me something about Ruby, its priorities, and value proposition. I'm very concerned about a language that claims it wants to be my friend.
Dunno, it's a comfy tagline. I never got into Ruby but it always feels to me like it's a really ergonomic and cozy language. Sure, the best friend thing is a stretch, but it's honestly a slogan. How many people land on this page with no knowledge of what Ruby is and will confuse it with an app to make friends?