In all fairness it has been done in the market now, more than once. So it's not as odd a request as it used to be.
So you want SWToR players to wait around for the next 7 year waiting on that "new engine" like the players of Anarchy Online have?
Or would you rather the players be given 7 years of content in that time?
By the way, graphical upgrades such as LotRO and WoW have done over the years =/= new engine.
You can count the number of mmos that have had actual new engines added on one hand with fingers left over.
So yes, it is just as odd to request it now as it has always been.