It was always the walking tank thing going back to FO1. By FO3/NV they had basically watered down PA to make other armor types more viable as play options.
In FO1, you basically had to have power armor or you'd get sliced and diced by the end game encounters. In FO3 and NV, PA was basically a style choice since the mechanics of the game actually favored light and medium armors. It was really hard to top the effectiveness of Elite Riot Armor or the top end light armors once you had the right perks.
At this point PA is more cosmetic choice than a high value armor choice. Slowed movement, the strength bonus not being near enough to offset the weight of the armor, penalties to sneaking, the need for a perk, and the reduction/loss of DT versus small arms actually makes PA a sub-par armor choice.
I'm hoping that when they do PA this time around that the benefits of wearing PA are significant, even if you trade off other benefits. IE, it should be a real choice in terms of play style versus an obviously sub-par choice due to bad stat balance.