Not typical at all around here (Kansas) for walls. If I do see it, I would associate it with cheap tract housing.
As has been said up thread, on a scale of 1-10 on the home repair scale, this is about a -5. A cheap plastic 6 inch putty knife, a one pint tub of wall compound and a paint brush and you are there.
If you can walk and chew gum - on the same week, no necessary at the same time - you can do this.
My hall is textured, but that is from wallpaper not drywall. None of my other rooms have texture.
Knockdown and orange-peel type textures are pretty common on drywall. Sometimes it’s fairly subtle and you don’t really notice unless you are looking for it (or trying to match it on a repair). I don’t really associate it with cheap housing.
All drywall has a texture. If you think it has none, then it’s a “smooth” texture. That’s actually the hardest to do because, as noted up thread, it shows every imperfection. But then, with “smooth”, there are different levels of smoothness, so maybe you have Level 2 Smooth texture, or something like that.
I have a slight orange peel type texture on the painted drywall in my house, it’s not due to an applied texture but due to my wife not sanding paint between coats. I am in total agreement with her, not a criticism, but that’s why my walls have texture.
I think it would be pretty fair to say that most professionals would never normally ‘sand between coats’ when painting internal walls (unless it was to repair a previous disastrous paint-job, or to clean-up plastered spot-repairs). They may occasionally sand lightly, in between coats, to remove any small imperfections but generally they’d try to avoid doing this by making each coat a winner.
The normal practise, before repainting, is merely to clean the wall with light ‘detergent’. (The generic product used in my neck of the woods is ‘sugar soap’).
If you end up with an ‘orange peel’ texture from ordinary acrylic paint it is a misuse of the product and not something that the manufacturer (or a professional decorator) would consider a successful application.