https://www.pcgamer.com/bungie-confirms-that-year-1-gear-will-carry-over-into-destiny-2-forsaken/

Good news for avid Destiny players: Forsaken won't make all of your Year One legendary gear obsolete. During E3 2018, I got the chance to sit down with game director Steve Cotton, design lead Lars Bakken, and project lead Scott Taylor to talk about Forsaken and, more specifically, its new hybrid PvE and PvP mode called Gambit. We'll have our impressions of Gambit for you later in the week, but during that conversation we touched on something that will bring relief to hardcore players. Gear dropped in Forsaken won't necessarily outclass the gear you've already acquired.

When The Taken King came out for Destiny in 2015, it reworked the way a number of core systems worked, and as a result Bungie opted to leave all old items locked at power threshold that couldn't reach the new cap. With Forsaken also set to overhaul key systems—random perk rolls are returning, weapon slots are being unlocked, mods are being improved—fans were worried that the same thing might be about to happen to the gear they've already amassed. But not so.