FOSS has a reputation for poor UX, and not for nothing either. Users who value slick, easy experiences tend to drift towards corporate software for basically all software solutions because corporate solutions can use money and the corporate hierarchical chain-of-command to respond to user requests faster than open-source self-organizing governance systems.

Ghost is likely what you’re looking for, a strong blogging platform with good activitypub integration.

Have you considered following a sport? Following local sports teams has always been an effective way to strike up a conversation for me. For one, it’s easy to identify who to talk to, since they wear apparel that identifies them as a fan of a team they follow, and also it’s really easy to know what they’re likely interested in talking about, since there are lots of resources (podcasts, broadcasts, blogs, etc) that direct the conversation. It’s super easy — I sat down on the bus yesterday across the aisle from someone in a Sounder’s hat and we talked the new Rothrock and Frei deals. I’ve never seen that dude before in my life and probably never will again, but finding common ground and something inoffensive to chat about was super easy because we follow the same team.