Yes I love Nostr and yes it is decentralized. But we are not battle tested yet. Is network able to handle attack of such scale? We simply don't know, yet.
Discussion
From Wired “but independent security researcher Kevin Beaumont and other analysts see evidence that some X origin servers, which respond to web requests, weren't properly secured behind the company's Cloudflare DDoS protection and were publicly visible. As a result, attackers could target them directly. X has since secured the servers.”