Add a pvp acquired stat to the new gear (like exp or fame) in the next expansion. But not new gear exclusively acquired in pvp.
In the past PL required pve to acquire better stats and gear to pvp (like 2pc/3pc ring, human faces, eggs etc).
Do that in reverse next expansion. Encourage pve players to pvp with stats and gear that make pve faster/easier (farming, leveling etc.)