You raise excellent points. But it was not my idea, it came from Tesla. So presumably they had at least theorized a method of operating a “battery station” to replace the “gas station”. I don’t know if they ever built more than a prototype that I saw in their video. But we do know they have deployed many of their own charging stations strategically. At a time, charging was free for Tesla owners who purchased before 2019 but now I think there is a fee for new buyers.
Presumably, if it was Tesla operated or Tesla franchised, it would eliminate the problems with interchangeability and warranty. They would own the batteries, and lease them to you 300 miles at a time (or whatever distance they can achieve). Perhaps, they would charge based on the range. A better design and ability to hold a fresh charge would eliminate other issues.
But yes, I don’t see that you can just swap a Tesla battery pack for a Ford pack or a Porsche pack.
For most people doing everyday things, it’s not a big deal. You charge it up at home, or at work, or at the mall (when they re-open :-)) etc. For road trips and distance travelers, truckers etc, it’s is an issue that drivers have to stop every 300 or so miles and wait around for an hour or more to recharge. As I’m sure you’re familiar, these batteries lose their ability to hold a charge. I’m still using an iPhone 6 for my own reasons, it is obviously several years old and I don’t use it all that much but it used to last 36 hours or so... now it can’t hold a charge for 12 hours anymore. (Perhaps Apple caused some of this with various updates now using more resources in the background). At least I get to run it down near zero before re-charging it which supposedly helps battery life.
Have you considered buying a ‘Morphie juice pack’ for your iPhone 6? It adds a bit of bulk; but, it would give you a lot more juice. They’re about $70 on Amazon. I think that’s cheaper than getting a new battery installed.