Can someone give me an overview of the eTAP series? From what I have gathered there are 2 generations and components are not inter-compatible because of the move from 11 to 12s and addition of AXS. What cranksets and cassettes are compatible with each generation of eTAP? All the promotional videos from SRAM seem to say that nothing other than their overpriced RED/Force crank/cass will work. Thanks for the replies so far!