The hate has always been there.It came back in ARR when people who took raiding too seriously in other games migrated to FF14 and tried to dictate their ways on the entire FF community.
Back with Titan HM you had constant rages and people flaming each other.Warriors got so much hate at this time too.It was basically pld or gfto.
Thornmarch extreme was also very toxic.As was Steps of Faith.List goes on and on.
In heavensward i think it was maybe the most cancerous stage with alex Savage to such an extent with tank dps that SE changed the way vit worked for tanks.
Nidhogg normal and extreme was really hateful too.Still is to be honest.

Best advice i can give you is to do content with FC.