What happened to Linear Tracking Turntables

After a lengthy discussion with a fellow audiophile who owns a B&O 4004 linear tracking turntable, he wondered what ever happened to the genre. According to him, they do less harm to the groove walls than do current arm geometries. He claims that records he has played hundreds of times sound basically the same as new with minimal wear. My response was--if they were so good, why do so few companies offer them? I'm sure there is a valid reason, but neither one of us is knowledgeable enough in the area to argue the point. Any analog gurus out there who could clarify the reason they fell out of favor.