Among all dlc and expansion, the only storyline that pushed the vanilla story forward is the Osinium DLC
(Considering you get to see prophet at the end and he says "we will never meet again", indicating we are past vanilla storyline)
(Also the old orc king dies and new king re-negotiate with DC)
Morrowind actually pull the timeline backward, as you get to be "pre-Vestige" in the game, only get killed later by Mannimarco.
All others, thief guild, dark brotherhood, imperial city and of course dungeon dlcs are pretty much stand-alone with no indication of where exactly those happened and if the three banner war is affected by those events.
(All we know is imperial city (at least white-gold tower dungeon) happened after mannimarco took power)
Do you want to see future dlc/ expansion take part later than vanilla game "by default"? (because you still can play orsinium first or morrowind later)
I personally really want to see the timeline move forward. Prophet mentioned "Daedra princes fighting each other" at the end of orsinum", so daedra realms are certainly in the later games. However I would love to see more about what happens to Tamriel
How the war unfold, who is the successor of each faction, will imperial legions rise again after repelling daedra worshippers etc. (<-Probably the only good thing with WOW storyline..you get to see the time passes)
So, question for ZOS is will we see it? question for players is do you want to see it?