This is something should have been discussed during the design before the construction of the pool started. now at this stage the step this will have to be re-designed and re-constructed.

At this stage, if you want wider steps, most likely the company will charge you more money to make changes unless they're willing to work with you and make a suggestion what can be done, they building your pool they would know best what can be done at this point.

Other than that, these steps is within code compliance and meet the min requirements.

Good luck

In addition to what GN said, remember that your stairs are designed to be used under water! Buoyancy is going to having an effect on how the steps feel to you.

Common name mistake-all good.

The steps can be made bigger. I'm not super comfortable about adding just a couple of inches of concrete on an existing surface.

It can be done though with the proper prep work.

For something like this, we have in the past created some sort of reinforcement to a thin pour by installing several Tapcon screws into the surface to create a bond. My preference is to use a non-shrinking grout (not a tile grout) over regular concrete.

The surface must be cleaned with acid to etch and provided an better bond. The surface must be wet but puddled, to allow the new material to bond. It must free of all dirt and dust. If the surface is dry, it will wick the moisture from the material you are applying and will not bond properly and possibly delaminate from the surface.

If it's very sunny location and it's hot, it should be shaded during the pour. After the pour the area should misted with a little water to keep it from drying to quickly.