EXPLOIT - to use (someone or something) in a way that helps you unfairly.
Danger close is the counter to Blast Shield.
By your logic, then the following are exploits NO COUNTER for these as well
Blind eye is an exploit because there is NO COUNTER for Killstreaks to be able to see them
Dead Silence is an exploit because now even Amplify can't hear them
Incog is an exploit because it renders Recon (another perk), thermals, tracker sight and motion sensors useless
I bet that you probably use those perks right?