No that is false.
The raids were merely the end of the progression that got shipped with the box. It wasnt before patches came along and added to the level 60 content, and started to balance everything around it that the idea of "endgame" started to seep into WoW. And even then one could argue that there were still the progression around gear at 60.
Dont take it from me either; Rob Pardo himself says as much:
https://www.idlethumbs.net/designern...b-pardo-part-2
A really underrated indepth look at the design behind vanilla, from arguably the single most influental person behind it. At around 37minutes in Rob Pardo acknowledges that there really wasnt any endgame at all in the shipped product.