Those are three _mandatory_ breaks, that add up to almost an hour, in ideal circumstances. To answer your question, not a whole lot, but in that 1% 6 hour drives aren't uncommon at all.
So if you really want to optimize you can actually do it with shorter 10 min stops. Check out Kyle from inside EV.
And until you can seriously deploy Hydrogen vehicles, it would be a few years down the road. Until then the next generation of battery an charging will be significantly faster already.
Practically speaking most people simply don't drive like that, people need to eat, pie and so on. With an EV you simply stop at a charger do all the things and go back. That usually takes 10ish minutes.
And to be honest, every road trip with at least on other person usually means a break every 3h anyway.
And even more in a day to day application, most people charge over night, so never having to go to a station and having a short break every few hours is vastly preferable to having to constantly go to the hydrogen station.
Of course hydrogen would also be significantly more expensive.
All in all, it simply doesn't make practical sense to optimize everything for this one specific thing.
I don't think I am. Camping vacations in Europe are very common. 1500 km in two days really isn't as uncommon as you might think. For clarity, I'm not saying it can't be done with an EV, I'm just saying the relatively many, long, mandatory breaks aren't nearly as convenient as the relatively few short ones that regular cars, and perhaps in the future, hydrogen cars, offer.
And again, taking a quick break to stretch your legs a bit, is not the same as needing to take a 20 minute break in order to be able to continue your journey. This might seem like a small detail but I really don't think it is.
I have traveled threw Europe all my life and the idea that 15-20min stops every few hours are a major deal-breaker is just nonsense. You want to pie, you want to eat, you want to go to the shop and get some drinks.
Simply stopping, plugging in, going to pie, get a drink in the shop and stretching your legs for 5min already adds enough to drive another couple hours.
And even if you are a case, where you really are driving like that, 1-2 times a year where you do journey like that the extra 30min you spend on the journey are really not the end of the world. I honestly can not describe it any other way then a small detail that wouldn't matter to the waste majority of people.
And even if that is still a problem, a few years from now batteries will be better, charging will be even faster and density will be higher. Hydrogen would not be the right answer.
Here in Canada things are way, way further apart than Europe and car travel to vacation is often many hours or days apart. I have taken a number of EV road trips and I have not had to stop more often or stay longer than I would have in a gas car. Charging speeds and range are only getting better, but they are already well into low/no impact territory.