I'd take easier approach to comparing BL and WB than philosophy:
Warband was fun.
Bannerlord isn't.
Hours you spend on game are just direct reflection of how much it keeps you amused.
Last couple of games I really liked was Little Nightmares, both of them take up 8hrs at most, but they'll stay in my brain forever because they're simply great. Same as other certain titles that I'll return to and keep playing, because they're simply good.
It's not the nostalgia, more like the fact WB brought something unique and original that wasn't there before, thus it was a bomb.
Bannerlord doesn't hold a candle to Warband, and is simply weaker, tacky product. Inferior version of Warband.
I have well over 2000+hrs on Warband, and every hour of that was spent well and I had fun.
Steam says 1039hrs on Bannerlord, and most of its hours was, well, pretty meh. Trying out barebones game isn't great.
Massive battles are nice. Graphics are nice. Sieges look way better now too. And that's it.
Where's the soul, the feel? The "zero to hero" way, why the shift from RPG towards realism? WB had this great arcade/realism ratio where you were a massive battle machine at 30 strenght that could take down a group of enemies, but too many foes mobbed you and took you down. Try charging into 3 dudes in Bannerlord, see how well that goes.
Skill system with perks that are just weird, giving you a % here or there, often scattered nonsensically in skills that have nothing in common?
The diplomacy, where is it? I remember how backstabby it felt when kingdoms were allied and they both declared war on your faction. Border incidents that could end up in war, or king losing his face.
Relationship with lords, where you felt people backing you up in decisions if they liked you? Helping others or leaving them to their fate, depending on how they liked each other? Campaigns that were make or break on relations, with hated marshall going around with 2 parties, while another everyone liked mustered a massive force?
Memorable companions, Jeremus getting knocked out in first 2 seconds of every battle is legendary. Ymira turning into medic and strategy master, Marnid into veritable war machine or pretty much anything you wanted out of him. And others, that disliked or liked others, leaving you if you put them together with someone they really hated? Because there was working relationship?
Memorable lords that had personality that mattered, dragging their own country into wars because they were just noble looters hell bent on pillaging, often jumping sides, or king's men that stood behind him to bitter end as their country burned down?
None of this is in Bannerlord.
All they had to do was take Warband, give it better graphics and engine (that's literally only thing that happened), maybe some more gameplay mechanics here and there, package it, stamp it, send it.
We'd have a supreme game and everyone would be happy. But no, Talewords had to go and reinvent the bicycle, ending up with a wreck with square wheels that's pain to drive.