I've had a few emails, and a few contacts over Matrix over the years. Barely any though. My email and matrix id are both on my front page at https://www.grepular.com. I recently added a "Like" button at various places throughout the site, front page, end of articles etc, so a click, followed by typing an optional message and another click is all it would take. I've been wondering if people ignore it due to assuming it is somehow connected to social media.