The combos were super static. Enemies never really reacted to getting hit. Days' primary form of dodging was also that weird air-slide.
While true your combo is static you shouldn't actually be using a gear long enough for that to become an issue. Early game you have little choice because your selection is small but mid and late game you should be changing your gears every few missions or so. It's a more extreme version of what we had in KH2 where every keyblade had is own use. The same goes for here every gear has its own uses and abilities and you're suppose to constantly change them to fit the world/mission/enemies. But it also brings back KH1's keyblade mechanics such as keyblades having different combo speeds.
It's also not true that enemies don't react to getting hit, it's just not every hit of your combo inflicts hit stun. Each hit either always inflicts hit stun or almost never inflicts hit stun. As there are a few enemies (generally the smaller ones) who will flinch from just about every strike regardless. Still as an example Take chrono gear (at least I believe that was that gear) the second hit always flinches so if you just go 1>2 1>2 1>2 instead of finishing the combo you can keep an enemy stunlocked forever. Not quite sure why they made it this way but that's still better than the near non-existent hitstun on mobs and bosses that would follow in games post-days....
While Days's primary form of dodge is same as KH1/KH2 it's dodge roll and glide. Air slide is largely meant for platforming and prolonging air time before you get glide, but later on when you get abilities that let you transition from an airslide to a combo and can air slide multiple times it does become an effective way to dodge in the air and with a lot more control than later version of air slide grant. While enemy combat in terms of dodging is kind of a hybrid. You've got a bunch of enemies that feel more KH1-ish in design where blocking isn't terribly effective so you want to use a timed dodge roll to avoid them. Then you've got a bunch of enemies that feel more KH2 design where the emphasis is is to use block, magic, and the enemies themselves to avoid being damage instead of dodging. And fitting both options have a nice wealth of customization options where you can make both your block and dodge feel anywhere from KH1/KH2-ish to BBS-ish...
Overall Days is basically a game that is sort of like an in-between of KH1 and KH2 gameplay. It's melee combat is a lot slower and more methodical like KH1 was but then mixes that with how KH2 had more mobility focus and trickier enemies. Same goes for the magic it's KH1-esque in feel and selection but incorporates KH2's idea that each magic should have individual uses/niches, and runs with that so not just every element but now every single spell works differently. Even the worlds have the hybrid thing going on where the KH1 worlds/sections were KH2-ified where they were made less claustrophobic and more linear while the KH2 worlds/sections were KH-ified adding puzzle elements and platforming where there originally wasn't much of.
Basically if KH1 was the child years and KH2 is KH1 all grown up then Days is KH1's teenage years. It's gameplay is something that is very much KH1-ish and has a lot of KH1's design mentality in it but also throws KH2 into the mix.