I don’t see the DF-21D or DF-26 as being mythological - just untried.
What's mythological is the idea posted on this thread that such Chinese missiles are almighty & unstoppable, no counter-measures, no escaping them.
The Chinese just click their mice and ZAP! Half the US Navy has suddenly disappeared in clouds of smoke.
I'm saying first: they're not that good and we're not that bad.
And second, sinking major American navy ships is an act of war, just as at Pearl Harbor, which would merit a response similar to WWII.
And if I remember right, our current pretend President said he wanted to be the greatest leftist president since FDR -- that would be his chance.