I'm liking Borderlands 4, especially its combat and gear; but I find its non-combat gameplay, NPCs, dialogue, and voice acting to be worse than most games in the series. Combat feels sparse and over too quickly even on hard, with way too much time spent looking for things on the map, fighting the game's verticality because of slippery surfaces and a lack of grapple points, and doing fetch quests. I love the build variety and weapons and wish I could be in combat for most of the time that I'm not in menus but am disappointed by the tedious and repetitive side content. And speaking of menus, I really wish they'd add the option to sort by type by default and fix the bug that marks the wrong item as junk. Lastly, while 4 is an improvement over 3 in this area, playing with friends online is still a bit laggy. I've always liked the Borderlands series more than the Destiny series, btw.
My biggest criticisms of 3 are the nails-on-chalkboard twins dialogue and accompanying music, the countless times I have to sit and wait for NPCs to finish walking and talking so I can progress, and too many drops overall with legendaries being too common. I love the DLC and gameplay. B4 seems to be addressing these and looks promising, so I hope it doesn't end up being bad.