I hate to say it, but depending on manufacturers for this kind of stuff will always inevitably lead to these kinds of situations. This is why I always buy OpenWrt compatible routers and DIY my own NAS.
Over the years, I've experienced:
- Netgear refusing to patch bugs like their IPv6 firewall essentially letting all traffic through on the R7800
- QNAP shipping NASes with Intel CPUs that had clock drift issues so bad they essentially bricked themselves. They then refused to provide any kind of support for them.
After that I basically said, fuck it, I'll DIY my own and have been much happier ever since. If you have the know-how and the time, DIY is the way to go for longevity.
I only have a few privacy-focused friends on Signal and Matrix and I talk to them that way. I have a few friends who use my personal Nextcloud and just use Nextcloud Talk to chat with me. For all others, I still use the mainstream platforms and just take care to not post any info that I don't want public and I make sure the apps have limited info and app permissions.
I think it is tough to convince others to switch until they themselves see the need, at which point they'll start asking you for advice on what to do.
With new contacts, I'll usually ask if they have Signal first and if they don't then I don't really push it. I think just getting the name out there every once in a while is the most you can do.