Both height and backstab advantage are overtuned, but I'd say backstab advantage is by far a bigger offender than height advantage.

Height advantage is at least controllable and deniable. It requires:

1) Elevation (relative to the enemy) to work. You are not guaranteed this every encounter. You can gain it with movement, but the enemy can easily deny it with their movement.

2) Not having someone else in threaten range (which is far wider than melee range). For better or for worst, most legit monsters in the EA have space jam level jump.

3) Line of fire to work - minor, but a refined AI or player can take advantage of this to protect themselves from ranged advantage.

On top of this, a specific elevated position can be made far less desirable by a surface grenade (which everyone seems to carry) or a level 1 spell like Fog Cloud.


Contrast that against backstab advantage. It cannot be denied (unless someone parks literally themselves into a corner). It doesn't even require a bonus action jump if you're not surrounded (you can just inch your way around someone to their backs).