True, but if you're just using phone and desktop, Signal works well. My point here isn't that Signal is perfect, just that the implementations by Signal and ot

True, but if you're just using phone and desktop, Signal works well. My point here isn't that Signal is perfect, just that the implementations by Signal and others shows that support for e2ee DMs on multiple devices is solvable. Teams can decide what their users need and how much flexibility is worth supporting. A public company of Twitter's size is clearly capable of solving this for some broad set of use cases.