No, it isn’t.
Two steps generally relates to the question of was a receiver in bounds after a reception.
Furthermore, watching the play in slow motion shows that he didn’t take two steps before he fell, he took one step, then fell, then essentially extended his other leg as he was parallel to the ground and only a few inches above it.
In fact, it really isn’t even possible to determine that his knee hit the ground before the ball did.
“Isn’t possible to determine” is grounds to not overrule the call on the field during booth review, according to the rules, right?