I talked about KDC earlier and it's only about weight. This is good too but I really don't like those inventory in which you have hundreds of (useless) items on your bags.
In games in which you have unlimited slots players pick nearly everything they can because "it could be usefull" and the inventory management is on the exact opposite :
=> You have too many things and you have to sort/throw/sell/put in a "bank" or something/...
Is that really better ? I don't think so... And even if inventory management is sometimes very slow/heavy in BG, I never had to choose between an item or another because I don't have enough slots.
I agree, having way too much crap that you have to sift through isn't good either. I think that the 5e weight limitations should be enough to limit how much useless crap you pick up.
Even if you end up with a 20 strength Fighter, your weapons and armor will eat up most of that Light Encumbrance. Plate is 65 lbs, a shield is 6 lbs, a longsword is 3 lbs, a longbow is 2 lbs = 76 / 100 lbs (+1/20 arrows if that's added).
That said, we'll have to see in the end. I also wonder how Bags of Holding will be dealt with. I think the closest game to do what they are supposed to is Pathfinder: Kingmaker.