It's all about inertia. Everybody either already knows vector algebra or will have to learn it anyway, to understand the vast majority of existing literature.

It's all about inertia. Everybody either already knows vector algebra or will have to learn it anyway, to understand the vast majority of existing literature. Geometric Algebra may be superior, but it's "one more thing" to learn/teach. It might catch on, but that might take another century of preaching.