Oh yeah - the Mayans, thanks. (Its been too long since I’ve listened to Coast-to-Coast!).
I have no idea about these gamma rays - but I would imagine that yes - they are “diluted” or whatever because they originated from so far away. (I suppose dispersed would be a better term?)
But a super flare from our sun, although tiny compared to this thing - because it is so close - yes, the EOTWAWKI thing. Every once in ahwile you’ll hear about a big flare that heads off in some other direction and they’ll say “If this had been directed at earth....” Of course - that was back when I listened to Coast-to-Coast more too!