Hm...I don't know guys..it is a fine line he's treading...
sure it needs proper attention and it is good he found it...
But...he tried repeatedly to access the onboard systems and was reprimanded repeatedly...this last attempt of his was successful...but it took tampering, the vandalization of another's property and the reckless and willful endangerment of everyone on board.
He could have accomplished the same thing safely demo-ing his technique to the proper authorities in one of the test simulation planes.
If no one wanted to listen to him...
I think it understandable why..
it isn't the 1st time he was caught tampering with a plane..

Hail him as a hero if you wish...
but if he had crashed the plane...
or if he manages to crash one in the future..
or someone in the future does...
Does he think it was worth it to tamper and vandalize property of another and jeopardize every life on board to be vindicated? ...to prove his point?
If it does happen ..expect that on future flights no electronics will be allowed anywhere but in your luggage in the belly of the plane..
or every passenger either restrained or sedated pre-flight to ensure the safety of all on board.
No matter what ..."some" vulnerability will always be found ...
At whatever cost ..passenger and crew safety must be ensured.