I think filters came first.  Both filtering amongst ISPs (quickly adopted) and for end-users (perhaps earlier, I'm not sure, but more slowly adopted).
Then followed the drop.
Of course, much of this drop is due to spammers finding targets other than e-mail.  Web forums of various kinds ... even wikis ... and recently Facebook, Twitter, G+ ...
I think I first received spam and/or attack email back in 1994.  By 1997, I had at least four different e-mail accounts, about as many aliases, and I had left behind at least two accounts (moved on).
The only reason I even vaguely remember ILOVEYOU &c was there was talk about them.  I didn't read any of them.  If there'd been a Gary-mail, I'm sure it would have been a notorious subject – even without the spreading to offline machines.  The contents would not even matter: Any geek would remember the event.