I Ctrl-F'ed the whole article, the word "fool" only appeared within the sentence: "I throught these attackers were fools".

So I think

> It starts with author calling his users "fools" for not randomizing useragent

Was not very true, given the author previously said:

> I thought it was a DDOS attack. I noticed everyone had this weird user agent that said it was a JIO phone. _I throught these attackers were fools_.