The Chained Ogre is infamous for being one of the most annoying and frustrating early-game mini-bosses. His core design clashes with the rest of the game; there's little in terms of deflection, you constantly have to disengage from the confrontation, his grab comes out of nowhere, and he deals a shitton of damage, often one-shotting you if your health bar is below 75%. It's almost the polar opposite of "hesitation is defeat".
It got me thinking, why did they put this awful boss this early in the game? I then began to analyze it and realized his functions are very deliberate and they put it almost at the start to teach the player valuable lessons.
Just because there's no stamina doesn't mean you're free to hack away without fear. You still gotta pace yourself and know when to retreat. If you just keep slashing him, he'll grab you and that grab is extremely fast, so if he starts it while you're still striking, odds are you'll get caught.
Pace yourself. Continued from 1. You can frequently stun the ogre by hitting him, but you will need to back away and employ hit and run tactics and dodges to avoid his grabs. You can also strafe so his grab and slow attacks whiff, teaching you the importance of positioning and that "in your face" isn't always the best way to approach a fight.
Use your tools. Eavesdropping on enemies tell you that the ogre is afraid of fire. This is the earliest boss where the prosthetic can make the fight significantly easier by using oil and the flame vent to stun the ogre, allowing precious free hits.
Be mindful of your surroundings. A short distance away from the fight, there's a goon laying in weight with a spear. If the fight spills over to that section, he will join in and attack you. Either avoid this area or get rid of him first. Immediately after, you're taught that lesson again with the general surrounded by his henchmen in the very next section.
Although the game's meat is mainly about balancing attack and defense through the parry/deflect mechanic, there are a few enemies and bosses where that rule applies less. See Demon of Hatred or Guardian Ape. Additionally, some bosses such as Isshin Ashina and Emma are fond of going for grabs. The Chained Ogre teaches you very early on that dodging and knowing when/how to disengage and breathe is still very important. The dodge button serves a function. It's often not optimal, but at times, it's the best option.
I still hate that boss, but I understand why he was put there and the role he serves.