I think they should have said 150MV regardless of the comparison, but some sort of "intuitive" illustrations is useful for non-specialists. But as other commenters have pointed out, millions of batteries is also unintuitive because you're trading an intuitive voltage for a completely unintuitive quantity.
I would have gone a different direction by making the voltages and quantities "almost intuitive" - say the electric field is as strong as hundreds of high-voltage substations (500 or so). Laypeople don't have an intuition on substations' physics but they do have an intuition on the economics (tons of homes and businesses depend on that thing) and therefore at least some appreciation for how powerful that voltage is. Likewise we can't visualize hundreds of anything, but we can (sort of) visualize a 20x20 rectangle and appreciate how many 400 is. So I think 400 HV substations is at least vaguely graspable.
I would have gone a different direction by making the voltages and quantities "almost intuitive" - say the electric field is as strong as hundreds of high-voltage substations (500 or so). Laypeople don't have an intuition on substations' physics but they do have an intuition on the economics (tons of homes and businesses depend on that thing) and therefore at least some appreciation for how powerful that voltage is. Likewise we can't visualize hundreds of anything, but we can (sort of) visualize a 20x20 rectangle and appreciate how many 400 is. So I think 400 HV substations is at least vaguely graspable.