This is no idiot light. When you hear how loud those buzzers are, they are impossible to ignore and you'll know there is a problem.

A blowoff is the last thing you want when overboosting the engine. The turbo is already spinning 155,000rpm loaded with pressurizing air, releasing that load will only make it spin faster. The risk of blowing a headgasket or cracking the head is peanuts compared to grenading the compressor wheel and feeding it to your engine.