I wouldn't try to analyse any sabre-ratting rhetoric by foreign leaders either way. But if you really want to: start with your own.

Google all the times the US leaders have threatened annihilation against foreign nations, threats vastly more credible as a global superpower.

One should never take words very seriously in geopolitics. They are 2/3rds designed for domestic populations, to propagandize them (esp. in democracies, which must lie to their publics), and 1/3rds lies for the other side.

Serious analysers of geopoltical strategy are only concerned with actions, capabilities and growing capabilities. And they are esp. uninterested in domestic propaganda.

Everyone in the US elite is extremely well-aware of this; by pointing to iranian rhetoric now they are just propagandizing american audiences to support a war of aggression which is, largely, against the interests of the US population.