I'm not an educator but I know from teaching my own children that you don't introduce math using symbols and abstract representations. You grab 5 of some small object and show them how a pile of 2 objects combined with a pile of 3 objects creates a pile of 5 objects.
Remember, language is a natural skill all humans have. So is counting (a skill that may not even be unique to humans).
However writing is an artifical technology invented by humans. Writing is not natural in the sense that language itself is. There is no part of brain we're born with that comes ready to write. Instead, when we learn to write other parts of our brain that are associated with language and hearing and vision are co-opted into the "writing and reading parts".
Teaching kids math using writing and symbolism is unnatural and often an abstraction too far for them (initially). Introducing written math is easier and makes more sense once kids are also learning to read and write - their brains are being rewired by that process. However even an toddler can look at a pile of 3 objects and a pile of 5 objects and know which one is more, even if they can't explicitly count them using language - let alone read and write.