He was also quite good at self promotion, as in the example of the Thomas Kinkade galleries that popped up like franchises in all the better custom frame shops in every town of any note at all.
Suffice it to say, there are equal or greater artistic talents doing greeting cards for Hallmark, but you don't see anyone clamoring to call their efforts “art.”
You'd be far better served buying antique animation cells from Disney classics, from an investment standpoint. Pretty much the same vibe as Kinkade, too, when you get right down to it. I always expect to see little elves or Bambi cavorting around somewhere in a Kinkade print anyway.
Evaluating art ends up being like evaluating wine. In the end, when you make it past the "nose" and "varietal" and even "color" (do a few black glass tastings and your Chardonnays and Merlots collide more than most know), it is about what you like.
The same is true for art. Norman Rockwell, in his time, was considered to be a sell-out to what we would now call Conservative Values. He wasn't "cutting edge." He wasn't changing the paradigm." But I 100% guarantee his "haircut" is extremely evocative (as a simple example). Art is what makes you feel good.