I feel like this is the perfect example of a fact that can be interpreted differently to support different arguments.
mRNA vaccines dealing with various coronaviruses have indeed been around for over 10 years.
COVID-19, being a novel coronavirus, needed its own vaccine, so a new iteration of the mRNA vaccine was created.
This is why soundbites are such a problem in science today. Too often, talking heads, politicians, etc. deliver information as single sentences rather than as long, complex ideas.