How did the community become this toxic?

[Zantetsuken]

The origin of toxic comunnity is when players are forced to do content, they dont like to do...
Mostly grinding is the source of that (farming stones to progress) and brickwall progress with lockout system...

What FFXIV really needs is some sort of Sandbox element...

Agreed.

An easy way is to allow players to find ways to challenge themselves - in FFXI, I remember trying to find ways to solo different NMs with RDM in my downtime and farming specific gear to make that possible. It was lots of fun, and a sub-community of players emerged who would share strategies for beating a specific mob.

In ARR, there are guard-rails on everything... Though Eorzea has the illusion of an open world, the game is as much of a corridor-runner as FFXIII was.