That was in the end phase of Vanilla after some broken patches. You shouldn't apply that to the whole period Vanilla was played. Some things that were done on Vanilla (i.e. t3 harb rush on finns) would have a very hard time today.
If you want to see the difference, you can just play the vanilla mod. (i hope its correct ported)
Games on bigger maps took often longer with big massive bases full of massfabs and other structures, completly shielded and t3 arty shooting each other and SCU groups as mobile economy scource i.e.
The much more "epic" experimentals were already mentioned.
Iirc, t1 arty couldn't outrange t1 pd and many many other minor things.