Hammer action is quite nice for learning piano playing. In my opinion it doesn’t have much value for sound design and composition.
Various weights, quality, styles of hammer action is how digital piano manufacturers create their specific playing character. If you were shopping for a digital piano, then I would heavily recommend a hammer action. I’d also recommend researching which company/model’s action appeals most to you.
For a midi keyboard, (generally) hammer actions aren’t as highly refined as digital pianos. They are more of a tacked on feature (again, in general). 88 key midi controllers commonly include it because they are flagship products. In my opinion, I’d buy whatever midi keyboard that has the advanced controller features you are after (e.g. chord memory, quick access controls, etc) and just use whatever action it has.