This isn't an issue with the IRC RFC.
This is a deliberate choice by EFnet, it's part of it's culture and bravado.
You won't see this on Freenode.
I'm not an expert, but isn't it more accurate to say that freenodes and other networks have "patched" the flaw via chanserv and nickserv bots to mitigate the problems with the network model? I know efnet doesn't want formalized chan/nick ownership, but they clearly dont like being the world's #1 ddos sink. Why not just include a master network quorum function and a grace period under which reattached networks don't get to merge their mode changes.
They mostly fixed the channel problems with CHANFIX.
This isn't really about that though.
Efnet has had chanfix for quite awhile now, which makes taking over channels from a split much harder, if not impossible.
Really? Hmm. It has been 5+ years for me, my bad. But what's the point of the ddos's then? I see netflow graphs of huge attacks on major efnet servers on a regular basis.
I'm honestly not sure why people still DDOS servers these days. Maybe just fun and games, it is EFnet after all.
Not too long ago there was an ircd exploit that killed servers and split 100% of efnet, which had never happened before. Not to mention its down 50% of its user base from a few years ago. Tough times for efnet.
Kiddies are DDoS'ing to annoy other users and to prove that they are capable of taking down the nodes.
All servers on the largest IRC networks are very well connected to the internet and servers that are not, wont be able to last long on these networks.
Some IRC servers wont allow you to create new IRC channels during a network split, so an attack where the network is being split constantly can cause quite a lot of annoyance for the rest of the users.
I mean it's only been a big enough problem for 20 years now that you can't even host an ircd on most standard hosting contracts.