Double Special has been "the meta" for hard content far longer than that. Before Mint, before Praxic, there was Choir. And further still there were Rocket Sidearms. It's only gotten more prevalent than ever because of how easily abilities clear adds now, letting you use nearly all of your ammo on bosses; since Special weapons hit harder and with the right build ammo isn't much of an issue, you're going to see a huge drop off regarding primaries. Primaries definitely need a buff to warrant using them but I don't think they'll ever get a strong enough buff that wouldn't just make them overpowered due to their "infinite ammo" nature.

Well, people has been running double special weapons since Lightfall, if not earlier.

It was technically the meta in shadowkeep but wasn't really popular till Beyond Light, they tried nerfing it between Beyond and Witch Queen I believe (Reduced ammo when using 2 specials I think it was) but it didn't do much. They tried to encourage exotic primaries with a 40% buff and finders got an extra 10% to the hidden bar value if using a primary and especially exotic primary but they nerfed exotics down to 30% and the new system uses a stat (Ammo generation) meaning you can easily just slap on an ammo gen mod and now your special generates as much as a primary.