Yes, I take secure messenger recommendations seriously; bad ones get people hurt. Tfiles have been passed around about the harm that has come to people using two other then-popular "secure" messengers.

(Matrix is very cool and I think it has a bright future as an IRC replacement and ultimately, perhaps, a Slack competitor --- something that provides opsec suitable for a commercial setting. I always come across as a Matrix hater in these threads, and I do not hate Matrix, and wish the project well.)