The Echo has a floating articulated hinge. Ask an Engineer why you don't see many of those in use.
You can ask, and the answer would be "it depends." The final result is a combination of the concept, design, and implementation. You're only on the concept of a floating articulated hinge. The design would include the final layout as well as materials. The implementation would include manufacturing procedures and quality control.
The easier the concept, the easier the design, and as a result the easier the implementation.
However, a difficult concept does not at all imply a failure in the final product.
At some point, they may be in a hurry and end up twisting the hinge sideways as they try to close it.
I'm starting to suspect you haven't looked at the Echo's design all that much, given this comment and the confusion on materials.
The articulating arms are connected together across the base hinge. We know the material is "metal", whatever "Super Copper Alloy" may be (marketing terms are fun and that could mean something as simple as brass but doubtful). I have to get a feel for this in the store (also, something I doubt you have done), but I highly doubt anyone would be able to twist it in a hurry...
Despite the arms not floating, I still believe the floating name does still hold. Mainly because of the upper hinge. as the top panel and slide forward or backward to lock itself in. This is likely a limited one-axis float, probably with long pins in tracks on the top panel to limit off-axis movement. Again, I'll hold judgement until I get a much closer look and feel.
But do not imply that since I'm arguing against you that I am arguing
for the Echo. I think the concept is great, but all dependent on the final implementation. Since the concept is difficult, reaching a good final implementation would be many times so.
Still, I want to get a good long look and feel before I pass my judgement onto others.