Signal has its own limitations. It wasn't that long ago that you couldn't use it on tablets at all, and Android tablets are still unsupported (even as linked devices). There are other weird limits on linking, too - e.g. why can't I have a secondary phone as a linked device? Why can't I have more than 5 linked devices in total?

Sure, it's a rare case of a project which is sponsored and paid for by a billionaire. I wish there were more such projects, but you can't base an economy on charity from billionaires.

*for now