I kinda feel the opposite - they can't afford to have the standard trim be a hole in their data collection fleet, and predictable services revenue (like connect+ and autonomy+) is a very attractive source of profits from those customers.
My working model, which is mostly conjecture, is that 2028 model years for the R1S, R1T, and R2 will all be manufactured exclusively with the gen3 platform. Rivian will switch R2 production as soon as January 2nd to integrate gen3 autonomy.
Ordering-wise, I suspect we'll see things laid out...
Different vehicles have different drag coefficients, but eventually drag is the dominant factor affecting efficiency. Sounds like dropping lower really helps the R1.
If your numbers held up in a controlled test for the R2, it sounds like it has become dominant at 70 mph. For example, I'd expect...