There’s crossover in that they both do compositing but AE uniquely has a lot of other things from the motion graphics side that just doesn’t exist anywhere else.

Does the integration of Krokodove into Resolve 21 close that gap at all?

In my experience, it's not easy as After Effects. Though for simple VFX, motion or animation is doable.

For me best alternative to AE is Blender.

Yeah this is the way. Blender has a higher learning curve than AE but it’s ultimately much better at actual 3d than AE is, and the recent improvements to the interface have made it a lot more usable.