This is exactly how a lot of people feel about this game. There's no joy and celebration after beating a hard boss here like in Souls. There's just this thought "glad it's over" until the next roadblock which happens after 10 minutes because the game is choke full of bosses/ mini-bosses.
Yeah i wanted to say, this is also a thing.
It's weird because i like the Sekiro combat more than any other FROM game, it's satisfying to constantly attack, put pressure on a boss, break their posture when they're still at half health, it's satisfying to deflect etc, but then the game as a whole just feels paced wrong.
Levels in between bosses are complete push overs, you may die here and there, but compared to the slow exploration of past games, it's something you completely breeze through, and i know comparison with Souls isn't fair, but the resulting loop is a series of incredibly hard walls (bosses) that feel way too close together, because everything in between is just noise.
Even if you compare it to other action games, Sekiro feels worse - Ninja Gaiden and Bayonetta for example don't feel like a collection of bosses stringed together by thinly veiled treks through cannon fodder, Ninja Gaiden in particular asks you to pay attention in levels more than bosses, in many areas.
Sekiro has to pull 100% of its challenge from bosses, and this creates a really weird difficulty curve, of abrupts starts and stops.
In Sekiro, i had just finished the Owl after 6 or 7 tries, so what i'd consider a fairly tough fight, and not 20 minute later, i'm asked to do True Corrupted Monk? I didn't even get to enter the Fountain Head Palace/see a new area, and already i'm expected to spend another hour on a boss (granted it was a rehash, so i sort of knew its moveset), so i said fuck off, and used the stealth kill glitch, and dropped the game for good soon after (after the Dragon).
In this sense, as i mentioned before, i preferred the approach of Demon's Souls which sure, had some
bad gimmick bosses (and some good gimmick ones), but at least tried to make every encounter different and unique, not just put another guy with 3 health bars you have to memorize a completely new move set of, every 20 minutes.
I don't mind the fights themselves, it's why i think a mode where you can freely fight individual bosses would even be fun, but as a whole, in the game, it never allows you to feel satisfied, when you spend 2 days beating a boss, and you're kicked in the ass by a completely different guy 20 minutes after, and you have to start all over, with very little in between.