For sure, but I'd say it started before Archaeology. It was just gradual. I agree Archaeology was the tipping point though, the point where it was felt.
But take the EDs for example; Those are full of lore, are pretty much entirely PvM content from a gameplay perspective, and yet if you go back to Temple of Aminishi's release it predates Archaeology by almost 2 years.
Simultaneously, they're a distinct shift from when we got Araxxor for example. "There's a really big angry f**koff spider boi in a hole over there. That's it." It took years for Araxxor and Araxxi to be retroactively labeled Colossi, and we still don't really have any other information about them; There was going to be an Araxxor quest at some point but it got shelved/never made it into the "planned" phase in the first place.
The distinction with the strategy of the EDs as opposed to the EGWD is that the EDs follow the model of Mazcab - they set their own story and aesthetic, separate from the "main" story of RS (although there kind of wasn't one at the time, we were still in a holding pattern after Endgame). The EDs do a better job than most similar things by making a high degree of effort to integrate into the existing world (characters like Bryll, recurring stuff from Ports and the Arc, dragonkin, etc) and also by starting and finishing a story across a short series of updates rather than leaving it hanging.
The EGWD though works quite differently to this by being part of the main story, in terms of quests leading up to it and out from it - rather than a story separate from RS, EGWD "is" the story of RS during that period.
Funnily enough Archaeology was also intentionally developed not to plug into the main story. There's more to say about that in a future livestream or something, but the inclusion of Archaeology into the story is very much retroactive rather than planned.