I’ve heard stuff like that too. To be fair, if the United States were to resolutely defend Taiwan, China might not touch it, though there would still be a possibility, but at the least the US and Taiwan would likely win that war since they just need to keep Taiwan independent, not invade China.
A neat thing about living in Japan is that there are announcements and signs everywhere telling you to please keep your phone silent and to turn down the volume on your headphones so that noise doesn’t leak out either. ‘Silent mode’ is literally called ‘manner mode.’