I guess it depends on the person.

200 miles more than covers all of the driving I do on any normal day. Today is an exceptional day, and I'll be driving a total of 120 miles for work. The Slate would cover that just fine with a ton of breathing room.

I do take far longer trips than that for pleasure, but they're rare.

I think if I only had an EV to drive, and that EV could only do 200 miles on a charge, then I'd be able to figure out how to make these <5% events work for me.

(I can use a break after a couple/few hours on the road, anyway.)

It does depend on the person for sure. I can see 200 being adequate for many cases. It's even still something I'm considering. I'd like to get a small truck again, they are just so useful if you are a homeowner, but I do a 220 mile drive about once a month and that's often enough that I'd ideally want to have that covered. Stopping for a top-up charge on a bathroom break might be OK, but I haven't ever looked at the locations where that would be possible, and if there are times when a wait would be likely, etc.

Once you reach a reasonable threshold, fast charging is more important than capacity. 200 miles is that threshold IMO, but Slate is "200 miles doing 55 in the summer". I want "200 miles doing 70 in the winter". And the Slate's charging isn't particularly fast: 20-80% in 30 minutes.