I, too, am playing Sekiro (PC).
I dragged myself through Dark Souls back in the day, and while there's obviously something compelling in there, I mostly found it be a joyless slog and was relieved when it was over. I hadn't intended to play another one of these From games, but it sounded like Sekiro stripped out a lot of the obtuse bullshit and sadistic punishment, and I'm glad I relented.
I like this game much more than Dark Souls. Just on a moment to moment basis it feels much better to play, and the grappling hook makes it fun and easy to get around the game world and avoid and escape fights as you please (often including bosses). And boy is it a relief not to have to worry about fiddly loot and builds and potentially screwing yourself over.
As for the difficulty, I initially found it overwhelming, and got destroyed by the early ogre miniboss. I put it down for a few weeks, and when I came back I dusted that goober on my second try. After that I was pretty much gliding through the game, though I tended to bolt from boss encounters and keep digging through to new areas. I finally hit a wall, though, at the bridge knight, because I hadn't actually learned the parry system and was relying on juking and jumping around, which did not work at all here. After like two hours at this chokepoint (and turning the settings down to make it snappier), I finally had a handle on the core mechanics, and realized this boss was not hard at all.
After that, I returned to the flashback estate, and killed the drunk guy on my first try. Shortly after was the apparently infamous butterfly woman, who I beat in 15 minutes. After more hours of dinking around and finding most of the health gourds, I went back to the castle and hit Genchiro, the biggest difficulty jump so far. This gave me some trouble, but after an hour I became numb to the intimidation of his final phase, and just rode the motherfucker and busted him in like 40 seconds.
I'm sure some true horrors await further in the game, but I'm feeling pretty chuffed about how I'm riding the curve. I have not hit a point as in Dark Souls with the gargoyles or Smough and Orstein where I gave myself another couple tries before I just gave up on the game entirely because it was making me miserable.