* The Emperor has no clothes. Dungeons and Dragons suffers from the very thing that makes it great, all you actually need is imagination. Any rule set and you simply can know in your mind and explain to players. There are many open rule sets if you want a rule book. Thus, there is literally no reason to buy any of the books, figures, etc. unless of course you want them. But then, this is exactly why Wizards of the Coast tried to kill the open source gaming license retroactively. Because they sell a product that is simply a shiny veneer over a person's imagination. I would say games like shadowrun and vampire: the masquerade do a much better job at this because they have created a rather interesting world for characters to participate in. While dnd has scenarios, i never found them all that engaging compared to whatever it is the DM or myself would create.
* I started traveling and doing fun things in the world we live in and I stopped having fun in the imaginary world of dungeons and dragons. Simply put, it takes a lot of time to play dnd and I could be doing something else. I have had a lot of fun playing dnd throughout my life but it takes a special group of friends to play with and that only comes along when it comes along. Simply playing for the sake of playing is not fun.
* all of the online tools, apps, and all of the various technology that people want to bring into the game destroys the game for me. Why? Because every single piece of technology, even the technology of pen and paper and books takes away from the improvisational collective imagination that occurs in the game. Of course character sheets give players artifacts that represent their players and helps them feel connected to the game. But most other things, other than dice always seem to rip people out of the game and suddenly you are searching a book, app, etc. to find the rule to figure out how to do the thing instead of simply relying on the DM to decide how it should be done.
Maybe I have become overly opinionated about this having played an enormous amount of dungeons and dragons, shadowrun, vampire, starwars saga, and every other system that someone wanted to try sometime because it either was attached to some kind of show/movie (although i never played a star trek rpg) or it was a new system that promised to engage the imagination more. But I dunno, I kind of gave up. Also, I DM'ed every game I've played for the 15 years. Maybe I just became jaded. Anyways, essay over.