ok - I will rephrase.@ct0517
The best linear tracker tonearms use the same force for movement across the record as a pivot arm - the groove.
That suggests the possibility of an air bearing.
I don't have a business relationship with Triplanar, just for the record. I do own two of his arms.
I saw a linear tracker eventually fatigue a Sumiko Boron to the point that the cantilever just fell off the cartridge. No particularly bad-ass records used. Prior to that happening, you could see the cantilever move from left to right. Clearly too much compliance.
I owned a Rabco for many years. I built a servo for it so that would be reliable. The servo also took some time to spin the motor up or down; in this way it would establish a speed depending on the cut of the record and didn't make a lot of motor noise. I also replaced the arm 'wand' with a carbon fiber setup that was lower mass. But the track that the arm ran on was its downfall- the track had resonance issues and used poor bearings to support the arm.
When the air bearing arms came out I took a good look at them, as I spent a lot of time at our first dealership, who also carried the arm. It gained a reputation for eating cantilevers. Clearly whatever cartridge you are using is more durable- what are you using?