Most granite is not glass smooth. It's pretty rare, actually. If you look at slabs with the light shining at an angle, you will see tiny pits, fissures, and small rough spots where the crystalline structure is exposed. That's perfectly normal.

The counters in the kitchen have had MUCH more cleaning than the others. Probably at least 20:1 ratio. That has removed all of the small rough crystals that were at the surface vs. the other counters still have most of those crystals intact. Rub them with a bit of steel wool, and that should finish "shedding" them.

I wouldn't bet that the kitchen counters had much more cleaning than others...my son was living in the house
I went to my current home and my granite here is same smooth, polished feel as kitchen counters in other house...I am more and more convinced the fabricator either omitted the final polish step or they just didn't seal the other counters maybe...
They were running late with the installation and my contractor was pressing them...If I remember and they were supposed to return and seal them a day or so after the install...but I don't remember watching them do that
Just the installations...

I think you could be onto something. Whomever came back to seal the countertops may have been different than the installers and thought it was just in the kitchen and thus the others weren't sealed.

Or if the bath countertops were cleaned with something more abrasive would be another option.

Granite is not polished at the fabricators. It's polished at the production facility where it's sliced from giant blocks like bread being sliced. It's why you can go to a granite yard and find bookmarked slabs. When it's sliced, the two adjacent faces are either smooth or rough. That facilitates transport so that it doesn't have a rough side against smooth.

Also, sealing granite has zero to do with it's texture. It penetrates the stone's pores, nothing more. It's not a topical coating like you put on wood with polyurethane. There is no physical change in the texture of the stone between one with sealer and without. If there is, it's typically caused by too much sealer being applied and it would need to be stripped to start over.

I bought 3big slabs from a set of 4 from granite supply house...
Are you saying that what the fabricators did to cut/shape the specific counters had nothing to do with their surface smoothness of finished product?
I find that difficult to believe especially when I can find on uTube videos of granite being worked with various levels if grit polishing pads for different finishes...