Trials of Osiris is making the long-awaited return in Destiny 2's Season of the Worthy but the seasonal Artifacts caused worry among the community due to the mode being Power-enabled. Bungie calmed everyone down by announcing they will not work initially.
Destiny's Trials of Osiris were the hardcore PvP mode where one would go explicitly to win and eventually end up on the Lighthouse, provided they had a flawless run.
However, another characteristic of ToS is that the mode will have Power advantages enabled in Destiny 2. Normally, this wouldn't be much of an issue since anyone who is serious about PvP will have maxed out their gear by the time Trials arrive.
Seasonal Artifacts, on the other hand, level indefinitely and can provide significant advantages to those who keep grinding bounties and other activities that award experience generously, most of which are in PvE. The conflict here is obvious as PvP players are not fond of having to farm PvE in order to be on equal or better footing in the PvP activity that is the highlight of the week.
On 28 February 2020, Luke Smith confirmed that Artifacts will be disabled in all Power-enabled PvP activities in Season of the Worthy, meaning that both Trials of Osiris and Iron Banner will ignore the Power boost given by the passive gizmo.
The Artifact suspension will not be indefinite though. It will only be in place until a Power cap is implemented so players can't just level it indefinitely and have an advantage in PvP because of it.
Bungie's aim with the Power cap is apparently to "weave Artifact and Power pursuit together" while "preventing unbound Power growth in PvP".
In other words, they don't want to make the Artifacts meaningless but also don't want them to be overpowered in PvP. Until such a compromise can be reached, the Artifacts will be disabled in Iron Banner and Trials of Osiris.