It feels like most Lemmy/Kbin communities skew towards having a lot of CS people. Makes sense considering what kind of people would be interested in using the fediverse over traditional social media sites though.
It's widely people that cared about third party Reddit development, so they'd automatically have to have some basic understanding and care for open software. It doesn't take much knowledge of computers to understand this, but it also doesn't take a ton of knowledge to understand this meme.