With advancements in this technology, there is now an experimental treatment to cause DNA mutation within humans to make our colds 'less symptomatic'.

It sounds like you might be confusing CRISPR and the mRNA COVID-19 vaccines. The mRNA COVID-19 vaccines do not use CRISPR and they do not alter the DNA of cells. They deliver mRNA encoding a viral protein to your cells using a lipid nanoparticle. Your body then creates the viral protein (called an antigen) and builds immunity against it. But no where is your DNA being edited like CRISPR would do.

As our understanding of molecular biology advances, why wouldn't we refine and improve the definition of vaccine? At the time vaccines were discovered, little was known about how they worked. Now we understand more and have more advanced methods to achieve the same purpose.