Indeed.
I remember Usenet in the 90s being 50% interesting conversations mostly about niche topics and 50% randomly devolving into flame wars in larger communities.
Even "Eternal September" as a concept was something from around 1993/1994 right?
Same for the 2000s era online-bulletin-board. I often go to thegearpage.net and am appalled at the amount of shilling, dismissals and disrespect, but then I remember that in the 2000s the main guitar forum was Harmony Central, which was mostly kids calling other kids moms names.
EDIT: But coldtea makes a good point about some (IMO) more recent changes: tone-policing, excessive marketing. There's IMO also a different attitude towards curiosity today.
I am remembering the same Internet. I got into lots of flame wars on comp.software-eng and before that on Compuserve and various FIDO boards.
It was never a very placid or friendly place. There was more tolerance for vigorous debate than there is now. The debate didn’t change many minds, I suppose.
Discussion quality is, in my experience, mostly a function of group size. Online discussions scale better than in person, but there's a limit.