FYI, Home button option features are available under settings/accessibility options/show navigation bar. Disable this option to get mBack functionality back. However I support your point whole-heartedly. I bought this device with a strong notion that hardware mBack button is superior to any other alternative software or hardware solution. I cannot imagine why a developer would force the option "show navigation bar" be enabled by default out of the box to get so many users confused.

BTW, a while ago I asked the developers, whether Flyme 7 global beta is coming out to our device anytime soon, and they confirmed. At least there is a reason to stay optimistic.

Stay tune