It's amazing that synology would hold themselves back with a proprietary app when they are trying to sell hardware and are competing against Google and Apple.
Synology is selling an experience, like Apple, not hardware. It's a plug-it-and-it-works private-on-premise cloud. They are not competing with Google or Apple in the sense that customer usually decide on-premise or cloud-based and only then look for a solution (prices are on the same scale, so the reason to choose one over the other is usually not price).
You could still run docker on the x86 models and host one of the solutions mentioned here.