I was using all lowercase as my default for internet comments (and personal journal entries) for at least a solid decade, starting from some point in the 90s. I saw it as a way to take a step back from being pretentious.

I eventually ran into so much resistance and hate about it that I decided conforming to writing in a way that people aren't actively hostile to was a better approach to communicating my thoughts than getting hung up on an aesthetic choice.

Having started out as a counterculture type, that will always be in my blood, but I've relearned this lesson over and over again in many situations-- it's usually better to focus on clear communication and getting things done unless your non-standard format is a critical part of whatever message you're trying to send at the moment.