Correct. In fact when hovering the electric fans will impose a higher engine load than a conventional shaft driven tail rotor due to the lower efficiency of electrics.
However as forward speed increases, the electric fan speeds can be reduced or even stopped. Therefore the electric fan load on the engines can drop below that of a conventional shaft driven tail rotor.
Another factor to be considered is the impact of reduction in main rotor speed to reduce noise. Many helicopters today have the capability of reducing rotor speed to reduce noise. This results in reduced lift capacity and engine efficiency. The ability to reduce the tail rotor speed independent of the main rotor speed may allow for additional performance benefits.
Just a question Re the above comment?
For doing what a lot of helicopters actually do, would a conventional tail rotor be better? A lot of helicopters are already maxed out when lifting heavy loads close to operating limits, and pushing a bit too much TR causes spikes that the computer loves to record for you. AS350 being an example. If the electric fans will draw more power than conventional TR, then surely they would be worse in these situations? As forward speed increases the draw on the conventional TR also decreases, but they aren't near the limits at this point.
So for operations such as Fire fighting, Utility, construction, Agricultural, lifting, logging, SAR if lots of winching, etc a conventional TR would probably be better??