I don't have an answer which is likely to satisfy you. I'm still a grumpy old IRC user. I communicate with non-technical friends and family via email, SMS, and Jitsi Meet. I allowed myself to be persuaded to try Matrix earlier this year and so far I've regret it.

goodpoint's answer is probably the best longer term answer: someone needs to fork Signal and manage it properly. But it's not as simple as just rebranding the software, it needs lots of difficult technical work to fix its many problems.