The advantages seem purely theoretical and you have yet to establish the need for an ETR.
Millions of hours flown with the conventional tail rotor in all aspects of the helicopters versatile roles and the number of TR failures and malfunctions is very small.
One crash with an as yet undetermined cause but some form of TR issue and you are proposing ETR as the saviour to that scenario and ignoring the realities of system failure/loss of power in the ETR, not to mention that many of the solutions, such as jelly's, ignore the amount of time many helicopters spend in the hover as opposed to the high speed cruise.
Keep on with your blue-sky thinking but I will be surprised if we see ETR in the next 10 years at least.
At what point have I ever proposed an ETR as a solution to tail rotor failure?
Why do you say I don't consider system failure or loss of power? The motor will meet the required failure rate as will the generation system. They are already multiple redundant systems.
All things start as theoretical. However analysis and testing so far have backed up the theory. Do you believe there are no practical advantages to a variable speed rotor?
I will continue, thanks, as long as there is a commercial incentive. I don't establish the need, that's done by either regulation or operational requirement. Whether that will happen with an ETR is out of my hands, but so far it has been worthy of attention up to an iron bird.