The comments here are a case study in conflict drives engagement. And not in a good way.

Try not to drive more conflict if you respond.

Facts:

The target audience of this post is someone who does not know anything about the dot product. It provides a mechanical/computational introduction. It does not include any geometric interpretation of the dot product.

Critique:

After you read the post, you should have seen something to connect to a matrix-vector product (imo), but the example matrices need to be transposed to look like a traditional matrix-vector product. Maybe the author is intending to multiply on the left by the transpose of the weight vector. The weights don’t seem to consistently appear on either side.