My first unfinished playthrough of Demon's Souls ended because I wasn't having fun. I went into Dark Souls, and believing that it was going to be different. It wasn't, but I figured out why.
Shields removed nearly every single threat from combat. You would block an attack, and then you would attack back. Pretty easy. No problems. Then, when you run into an opponent you can't block, and whoa, problems.
Just roll. There is only one shield in the entire series I would bother equipping, and that's the Grass Crest Shield, for that stamina regen.
You can roll through every single attack. You can completely avoided being locked down by O and S with some well timed rolls. Sif can no longer hurt you. The Four Kings are a joke, even if you don't use poise. You can roll through everything Manus throws at you. Kalameet steppy stomps no long stop you.
Without shields, tension returns to melee. Mistakes turn to death. Every enemy you can't kill in one hit is a threat. It's fun. It adds an element of strategy to every encounter.
So fuck shields. They are a crutch, and I'm glad Bloodborne is getting away from them.