Those days still exist. I am more likely to get answers on an obscure topic in a irc channel with 20 nicks than I am in a Discord channel with 2,000. The difference is in how easy it is to discover a channel and pop in even if it isn't a main topic of interest.
Discord et al make discovery and joining difficult enough that if you bother to jump through the hoops you will probably just stay joined even if you never check it again.
Then there is the segregation of topics within a server. On irc you never feel like you have to declare. "I say, Reginald old pal, shall we retire to the 'compilation issues' sub-channel? I've some niggling warnings I've been meaning to run by you." You always get the vague feeling you are off-topic and that squashes lively conversation.
I'd love to see a Nostr based irc clone with very simple structure and not even have to join an irc server.