It made me appreciate what good work linesmen(or whatever they are called these days) did before VAR. I mean they called most things right, the offside calls were by and large right decisions. Sure there was the odd bad decision but it was usually a close call. Now their job is mostly pointless, wave a flag after a goal is scored just in case and it'll be checked anyway.
Remember the times you felt silly for going crazy after a goal was scored only to see the flag up and realise it won't count? Pure emotion and excitement that has now been taken away. Now you can't celebrate a goal until it's approved and when you concede you just pray var has picked up on something to disallow their goal.
So I agree, very little to justify its existence