I think its unlikely that we're gonna see a whole lot of difference. I mean, at this point, it seems John Deere is for the most part "compliant" with all of the proposed regulations. The only area they don't offer software and the ability to DIY is for the engine emissions systems components...
See part of the problem is on your Amazon example, Amazon often provides way better customer service then these local mom and pop places. I order something wrong, they'll send someone to my house to pick it up. It comes in damaged, they ship me a new one before I send it back, or if I give them...
for me, its been really hard to "buy the dealer" because I have no clue how the dealer is going to be with the service after I buy it. Around here, the sales and service departments at every major brand are pretty much seperate. They claim they communicate, but my experience is its very limited...