My sixth grader and first grader score in the 90+ %ile in mathematics and didn't come close to learning multiplication up to 12 in kindergarten. In fact, the topic isn't even covered until second grade at the earliest.
I think establishing a foundation of addition and subtraction takes far longer for children to master than you're considering, especially since there is evidence that children of this age appear to intuitively view numbers logarithmically rather than linearly [0].
I suppose you could take advantage of this by somehow prioritizing multiplication and division over addition and subtraction, but I think there's too much value in comprehension of linear numbers and addition/subtraction since that is the lion's share of interactions they will experience at that age.
On the other hand, if you're merely talking about abstracting multiplication and division into patterns, then I wholeheartedly agree with you, and there is evidence supporting this [1]. Although pattern identification is already part of kindergarten/1st grade curriculum here.
Ultimately, IMO the most important aspect of education in general is covered in the open letter linked to the OP:
> There cannot be a “one size fits all” approach to K-12 mathematical education.
My children have thrived with their current math curriculum, and I know some of their classmates have struggled in contrast. One size does not fit all in education, nor in many aspects of life.
0: https://news.mit.edu/2012/thinking-logarithmically-1005
1: https://www.tandfonline.com/doi/abs/10.1080/15248372.2012.68...