I totally agree with you.
When I was an engineer the bulk of my work was with Matlab. And as you may know, working with Matlab is none other than working with matrices. Thus, Algebra.
Math is even more important when it comes to Data Science as it is the foundation of Deep Learning and Recommender Systems... .
Statistics, Linear Algebra, Operation Research, Graph Theory etc. All these step in when you train your models. However, my object in this article was the tools one needs to land a Data Science position rather than what lies underneath the hood of Data Science.
Although the particulars of Math contribute also to employability, I believe they should be the focus of another story.
For the record, I was introduced to Data Science by my Math professor at the university.