SMS support for signal isn't a big deal? Well, it gets people on board. So yes, it's that big of a deal. Without it, I have no way to convince people to switch. I had people switch before, and when signal dropped SMS I lost many of them.
And guess what, I live where that matters, so...
I'd also rather use SMS than any of those privacy violating systems. SMS isn't secure, but those systems are designed to be adversarial. And at least iMessage is far more secure than any of those, even with it's issues.
The blue bubble is an issue because we have so many iPhone users, and they, (like many Android users) , don't want to have multiple messaging apps. I don't agree with them, but I can't make them change their mind. I have probably 5 messenger apps, Signal, Telegram, SimpleX, Briar, an XMPP client or two, Wire, etc. I'll use anything that's reasonably secure to replace SMS, but I'm not going to jump into garbage like WhatsApp
It's really funny hearing you be dismissive of these issues yet ignoring there are at least 3 organizations working on interop, and lots of people signing up to use them. Want to tell them?
If it's not an issue for you, good for you. But then why do you care so much to tell others it's not an issue just because you can't see it?
As I see it, why are you using garbage like WhatsApp or FB junk? They've repeatedly shown they're not trustworthy. Oh, becuase you went along with what everyone else is doing around you, clearly without any consideration for who you're giving your data to.