The way these conversations are structured, I'm always going to come across like I'm rooting for Matrix to fail, which is not at all the case. Like I said, I use Slack more than any other group messaging system, and while Slack does have some security assets that Matrix lacks, nobody can say that it has a more coherent encryption story. I wish Matrix all the best; I just don't think it's reasonable to suggest it as an alternative for people who need secure messaging that reliably works in groups of people.