You don’t own an ebook, companies can and have modified and removed ebooks without the Kindle owners consent -see Amazon and the “1984” & “Animal Farm” ebook deletions- and there isn’t a large price advantage between physically printed books and ebooks, which was supposed to be a big difference between physical and electronic media. Amazon is the largest source for ebooks, not quite a monopoly but close. Yes there are sites with public domain ebooks that you can convert and load into your Kindle, either the device or the app, but the quality is even worse than standard ebooks and it requires (admittedly simple) extra steps to acquire.
You can’t give an ebook to a friend or sell the ebook. Technically when you die the rights to that book do also, you can’t leave your library to anyone. Right now the only real advantage is the ability to travel with hundreds, and if you have access to the internet, millions of books in a small portable device.
I was initially buying ebooks but with the costs, map/pictures formatting problems and the legal restrictions imposed upon me for using ebooks I have gone back to buying physical books.
You’re correct about the disadvantages you listed. It’s puzzling that digital books aren’t much cheaper than their printed counterparts. Especially, since sharing purchases is thwarted. It’s not surprising though that Amazon, which originated as a book seller, is opening physical bookstores to sell physical books. So relieved that bookstores and print aren’t kowtowing to a culture or generation that can’t read more than 140 characters at a glance.