You misread my post. I said as soon as they *do* need to switch formats (like owning multiple devices) then all bets are off, and they have to enter a whole world of technical concepts which the majority of readers out there in the world do not give one iota about nor do they want to learn it. Which creates a very big problem, because format shifting (and stripping DRM since you added that to the discussion) is a case of diving into the deep end of the pool, there is no way to just gradually wade into the shallows.
DRM stripping cannot even be publicly discussed let alone be placed at the forefront of a calibre feature list, so while it remains illegal in many countries it is always going to remain an activity precluded to those who have a certain technical level by the nature of knowing where to go, how to get it, how to set it up, how to update it etc. And without it, you are not going to shift formats, which means you aren't going to be using one of the primary purposes of calibre.
I don't disagree at all with your list of basic function as a wishlist. However the point in my post above was that once you take out the top two (which are not possible either for technical or legal reasons) you end up with something that other programs already do. And by trying to include those top two, by their very nature you require a certain technical level that users like my parents are never ever going to be at or have any desire to do so.
I didn't invent ereader formats, heck I would like nothing better than to have some single standard that every single ereader used that accomplished everything everyone wanted so we never had to shift formats. However back in the real world that doesn't exist.