Does this mean that someone having a likely heart attack should have someone drive them to an ER in advance of paramedics arriving?

I’d say no if it were my family, and I know the response times in my area, but the story in the blog is a nightmare scenario.

People can go from heart attack to cardiac arrest quickly, and you don’t want to then tell medics you’re on the freeway and now need to do CPR.

See: https://m.youtube.com/watch?v=mxUqHwHbNtk&t=1520s

Around the 11 minute mark this man went into cardiac arrest, a moment prior was still talking.