The point is that the types of problems you're referring to aren't considered algebra problems in math education, because students are expected to be able to solve them when they are introduced to subtraction, not when they are introduced to actual algebraic concepts. It's like saying when you learn to add integers, you're doing group theory because integers form a group under the operation addition. From a purely mathematical standpoint, sure, what you're doing could be explained using group theory, but from a pedagogical standpoint, it's nonsense, because you don't have to know anything about groups to be able to add integers or even to understand and utilize these specific properties of the set of integers.

It's entirely disingenuous, then, to refer to these word problems being solved by Russian students in 2nd grade, as though it has any relevance on whether it's appropriate to teach Algebra 1 in 9th grade. 2nd graders in the US are also expected to be able to solve these types of problems and it's not because they are taught any actual algebraic concepts.