EV news, page-23

"So permanent strong magnets don’t work for it. It’s smarter than that"

Where do they say that it will only work with non-rare earth magnets?

Their method of varying the field strength will work with any permanent magnets, strong or weak. What they are doing is roughly as follows.
If you imagine two lines of magnets on either side of a gap.
And each line of magnets is comprised of alternating north and south poles facing into the gap so as to create zones with alternating field direction across the gap.
The peak field strengths across the gap will be achieved when each magnet is located directly opposite a magnet pole of opposite polarity on the other side of the gap.

However if you slide one of the lines of magnets along slightly, then north poles will be partially lining up with north pole on the other side of the gap and the same goes for the south poles. The effect will be a reduction in the strength of the fields in the gap because the magnets are partially cancelling. As this is bought about merely by an adjustment of the physical arrangement, it will work with any kind of permanent magnet.
(In practice the lines of magnets are wrapped around a cylinder or disposed around the disks at the ends of the motor, but the concept is easier to explain as lines of magnets.)

It might seem counter intuitive to want to reduce the field strength. However, as the RPM increases the back emf generated by the motor increases and that subtracts from the emf of the power source. Consequently, ceteris paribus, the input current to the motor will decline, thus reducing the output power provided by the motor. This can be overcome, either by increasing the power supply voltage, or by reducing the motor field strength and thereby reducing the back emf that the motor generates. In motors with wound field magnets (electromagnets), the reduction in field strength can be accomplished by reducing the current in the field coils.

Reducing the field strength is akin to shifting to a higher gear in an car with an IC engine.
It better matches the engine's torque and RPM capabilities to the road speed.

My background is in another field of engineering but fifteen years ago, I developed and built a microprocessor controlled, three phase permanent magnet motor controller from scratch and I have built three phase permanent magnet motors.

"Yes, the link, the second link, deals with their applicability in wind turbines - that’s where the quote came from."

Nope. Perhaps I have missed it, but as far as I can see the only mention of "turbine" in the second link that you provided is in the gimmicky name that they have chosen for the technology.

IMHO, this motor topology is not a threat to demand for rare earth magnets.
The topology would work even better with rare earth magnets.
But using ferrite magnets with it, might be something that you would resort to if the supply of rare earth magnets is cut off or is unreliable.
That may be relevant if Trumpet and Xi carry on with the pissing competition over tariffs.

Cheers