That's kind of a tautology. If you assume the system is insecure, then yes its going to be insecure with that assumption. This is going to be true of any VPN system, so i think its an unfair criticism to level against this particular VPN setup.
If you want to be secure against local adversaries, use TOR.
this is my favorite extremely annoying but massively useful "acktually..."
begging the question as a logical fallacy is prevalent in politics and media representations, and is a differentiatior between reasoned debate and talking head nonsense.
Polictician 1: UBI!
P2: free market competition!
P1: why do you want poor people to suffer, P2?!
P2: 2nd amendment!
P1: Ban firearms!
P2: why do you want americans to be put in danger, P1?!
If you want to be secure against local adversaries, use TOR.