HD should never have killed Buell. I get that Erik was kind of a dick to work with, but his bikes had (even still have) a loyal following.
...but, selling Buells in HD dealerships mixed as well as orange juice and toothpaste. Buells were tucked in the dusty back corner of most HD dealers. If you could even get a salesperson to talk about Buells the conversation went something like..."After you get bored with this 130 hp, 400lb beginner bike, you'll want to step up to the 65 hp, 900 lb Geezer Glide..." It was a terrible fit.
Buell support was limited to OEM parts (even tires) and Buell (HD) branded gear. You couldn't walk into a HD dealer and buy Michelin, Pirelli, Shoei, Alpinestars, etc. That model worked for Harley, but was a huge turnoff for more sporty Buell riders. There was once an argument within HD Marketing about why Buell (sport bike) riders wouldn't wear Buell leather vests. - this story was told several times by Buell insders.
It will be the same if the Pan American actually makes it to dealers. It will be only OEM tires and HD gear. No Mitas, or Klim, or Giant Loop...non HD, popular ADV accessories will not be on the menu & sales people won't know a thing about ADV riding.