Am I the only one who thinks this is complete overkill?

You might be the only one that thinks this is overkill.

49/52 weeks a year, I never use more than 15% of my battery on any given day. I don’t need 600 miles of range

Then this doesn't sound like you fit the use case, which is fine of course, but there are many that do.

• Delivery drivers that may have to go to far places without consistent EV charging
• Winter battery penalty. That 600 miles may be 400ish in extreme cold which many people on the planet live in for at least part of the year.
• Heavy loads vehicles. The 600 mile number is used for the basis of comparison to today's passenger sedan EVs. When putting these in heavy trucks, that 600 mile number may be cut down to 300 or even 200 miles, which opened up new avenues for EV heavy goods deliveries.

In short. Its not just about you.