I absolutely cannot understand this logic. Didn't you notice that the development of several Trek product lines has actually stopped? While Specialized are far forward with their latest Mastermind system and neatly organized product lines. There are only two systems, the full power one based on Brose, and the lightweight (totally uniform) SL system, all based on a single app. Trek are struggling to compete with Specialized on a lightweight e-bike, and so far have not come with anything such like the SL (used on road, gravel, fitness, trail, all-mountain, and city e-bikes). The latest attempt with the TQ HPR has been indeed brave but why release two separate product lines based on a no-name hub-drive motor? Also, did you notice that the "latest & greatest" is only used on the most expensive Trek e-bikes?
The tragedy of Trek is they have never owned any e-bike system but made themselves a hostage of e-bike system manufacturers. Bosch is coming with the Smart System and what happens? All good product lines suddenly become obsolete.
Many huge companies collapsed when they lost their sense of direction.
P.S. The SL being a "niche product"? That's the product Trek would die for to get! Trek has been always trying to follow Specialized on e-bikes. Spec making the Vado (Latin: "go!") and Trek answering with Allant (French: "go!")