I can understand why one would want to move from Kindle to another device, but this article starts by complaining that support is being dropped for devices from before 2013. I can even understand being upset by this, but I have absolutely no faith that whatever other device I switch to will still be supported in 10+ years. Could be. But I sure wouldn't count on it.
I don't love having to replace them, but paying €120 every five years is probably worth it. I mean that's €2/month, and I have a huge library of books which I load via calibre.
I read daily, on the bus to work, at home in bed, and while there are "more free" ereaders I've become accustomed to the kindle and have no complaints. If I were not so clumsy they'd last longer, so that's on me.
My physical library is pretty big, but being able to carry 50+ books at all times? And have a battery life of a few weeks? (I stay in airplane mode, as I transfer books via the USB cable). It's hard to complain.