Less friction when inspecting
Many players use Inspect to look at the gear and talents of other characters. In WoW: Classic it was a bit clunky. WoW: Forever improves this in two places: the range is larger, and talents can be viewed without addons.
Larger range
In WoW: Classic the range was tiny: you essentially had to stand right next to your target. If the target moved out of range, the Inspect window also closed automatically.
In WoW: Forever the range is increased and the window stays open even if the target moves away. You can look over party and raid members for as long as you like.
Talents at the click of a button
In WoW: Classic you could not inspect other players' talents by default, which is why many relied on addons.
In WoW: Forever the Inspect window has a Talents button that shows the target's chosen talents.
Original report: Wowhead