I have family members and good friends who are professional musicians - so can relate to this. We think life is a pure meritocracy where the best ideas, the best writing, the best songs, the best actors always win out. What you've so clearly illustrated is that the business part of any endeavor is even more important than the substance of the idea - if we measure "success" by sales.
Case in point: Some good friends have had an album listed in the top 20 by Blues Rock Review 5 years in a row. (They've cracked the top 10 in the past 2 years) Sure, Joe Bonamassa is going to win most years, but my friends are really, really good.
How good? I would put almost any of their albums up against anything the Eagles did prior to "Hotel California" (and post - "The Long Run") and it wouldn't be much of a contest. "Peaceful Easy Feeling" doesn't get 1% of the airplay it received if "Hotel California" hadn't shot to the top of the charts. After they are "discovered" however - "Their Greatest Hits" complied from their first 4 mostly forgettable albums becomes the best selling record in the US in the 20th century.
Dragonlance is like one of those sitcoms you've never heard of that runs for 10 years. It's a mediocre song that shoots to the top of the charts because it was recorded by Justin Beiber. Of course there is talent and skill required to produce those products - but there are so many other shows and songs 100x more creative that disappear without making a ripple.
Mostly muddled points here from my side - but love how you can show the business of writing, with actually tips to become better at that side.