This is exactly my feeling on the subject.
For the argument of "The Game does not teach you how to play"
- As you level up you gain small parts of a skillset in a linear order of how they are applied in a fight. All the skills have a reasonable description of what they do
Example
Straight Shot - Increases Crit Hit Rate by 10%
Venom Bite - Additional Effect: When damage over time is critical, there is a 50% chance Bloodletter and Rain of Death recast time will reset
Wind Bite - Additional Effect: When damage over time is critical, there is a 50% chance Bloodletter and Rain of Death recast time will reset
The game is not to blame for not teaching Bards that they should keep up Straight Shot and their DOTs to maintain a respectable amount of DPS to clear content, and yet somehow there are players that spam Heavy Shot and only use Bloodletter after it's manual CD Timer, even though BRD has it's basic DPS structure by the time you hit Level 12.
This is true for most classes in the game.
DRG - Heavy Thrust Level 12 -> SE saying that between level 12 and 38 we are only going to make you worry about keeping up Heavy Thrust and learn to weave in oGCD skills. See many Dragoons that don't use Heavy Thrust?
BLM - For 34 Levels between level 4 and level 38 we are going to let you learn the difference between Astral Fire and Umbral Ice. Since there isn't a great description on what the differences are that should be enough time to figure it out, "Right Ice Mages?"
I mean, that's just getting a skill and reading the description of it which is pretty straight forward. Then we have "The Hall of the Novice"!!!!! which actually holds your hand, step by step and explains to you what to do. This game literally force feeds you on how to play.
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As far as fights getting outdated and unavailable to new players, while that is somewhat of an issue of getting to experience those mechanics it is not a game breaker. A lot of the same mechanics appear in different areas of the game including Dungeons. So while they are dubbed down compared to their Savage counterparts or Extreme Primals, they are present and in a lot nicer learning environment for new players.