Set to strike earth? It already is disrupting radio communications.
1. I don't think this is "The Big One" but CME is no joke or hoax.
2. Look up "The Carrington Event" -- 1859. It energized Long telegraph lines (which had never existed before), and started fires in a number of telegraph stations from the energy so channelled.
3. I don't have the physics to explain it better than that, but SOME CME (almost certainly not this one) could do a lot of damage, with a lot more high-potential electrical stuff around. There are a lot of good solid serious double domes spending some legit time worrying about this.
4. Since there hasn't been one of the "Carrington" size in 150 years, it's not a high-probability, but not negligible.