Didnt the defender knock it through to Isak whilst making a deliberate attempt to clear the ball? If so then shouldn't this become a second phase of play and Isak is therefore onside.
No the rule is comical, the hand isn’t offside if it is line with the shoulder, in this case Isaks arm was outstretched
Offside rule should simply relate to feet and ignore any other part of the body. Attacker's feet position in relation to any defender'd feet position. At least that would get rid of this nonsense at least on body position aspect.