It heavily depends on previous experience. Whether the child is taught at home or attends a pre-school and what that pre-school is trying to teach. Education is a bit of a passion of mine even though I'm not a teacher (of other people's kids) so what follows may be long-winded. I'll try to stay on point and hopefully provide some value to the discussion.

Anecdotally, most of the pre-K programs around here (Indianapolis) teach toward Kindergarten preparedness, which is to say, they teach the alphabet and associated sounds and most of the digraphs and diphthongs as well, and for Mathematics generally counting as high as you can make it (most of ours target between 20 and 100), some simple single-digit addition, and shapes.

Kindergarten here focuses fairly heavily on reading. From sight-words to all-out phonics, reading is the primary objective. Kindergarten, however, is the year in school with the highest variance in ability between children, and as such can lead to very different perspectives. My oldest child is 6 years old and in 1st grade at the moment. He's a bit of an outlier though, so take anything I say with a grain of salt. He was easily ready for Kindergarten when he was 4. He has a March birthday though, so it would have taken quite some convincing to get the school to accept him early. His maturity level though, led us to keep him in pre-K and send him to Kindergarten on-time. Even so, he's essentially reading between a 4th and 5th grade level before he's even halfway through first grade. There are about 4-6 others in his school that are around the same level (99%ile on every test they're given). Others in his class have exactly the opposite situation. Some, are just not ready developmentally. Some simply aren't interested. Some kids have older siblings and are used to acting out to get any attention. Some of them didn't attend any pre-school at all. And some that didn't attend a pre-school receive zero help at home. My son's Kindergarten class (at the start of the year) had kids that ranged from having a 2nd-grade reading level to those that didn't know any of the letters of the alphabet. But they all generally are able to read around a 1st grade level by the end of the year. I have a profound respect for Kindergarten teachers after last year! Having a classroom of 20-30 kids of such widely varying abilities seems like a fairly impossible situation to me.

In any case, I can speak of my oldest son's experience a lot more than I can of anyone else. So, understand that what I say skews toward the high-ability scale. But I don't know of any Kindergarten classrooms that don't teach reading. I'd be curious to know where you went to school because that seems completely contrary to my experience. Our teachers sent home paper copies of stories for our children to read to us, and this started within the first month of Kindergarten. I'm sure the results were varied, but they taught it.

I went to Kindergarten in 1987 and they taught us how to read there as well. Some of us had a head start from what our parents taught us. Most of us didn't go to any sort of pre-school, and in general, all of us were 5 when we started. By the end of Kindergarten, everyone in my class could read around a first-grade level at minimum. We could do single and two-digit addition and subtraction and we were starting to work on memorizing the multiplication tables. We were taught some rudimentary music reading (notes on the treble and bass clefs) as well. Granted, this was an all-day Kindergarten at a private school (in Michigan) with a smallish class size (~22) but I didn't feel it was too atypical. It wasn't until I was in college that I learned that not all Kindergarten classes were full-day. And it wasn't until I had kids that I found out that a lot of things I learned in Kindergarten weren't "standard". But when I was kid, everyone could read by the time they were in 1st grade. Spelling and Vocabulary were all that was holding anyone back at that point.