This happened in the 0bama administration. It's been on our phones for years! And, not bypassable.
Correction: it's been on our phones since 1997.
This is uncharted territory for most employees in emergency response and management, since this would be the first wireless emergency alert from an American president since the EAS was put in place by the Federal Communications Commission in 1997.
Either way, it is not a Trump thing.