Reading this thread I couldn't help but remember my old beloved Nokia N900. Man, this device was a BEAST back in 2009. I still use it eventually, when I feel like OP and want just to update my regular Linux-distro on it, together with all its apps and services. Guys, the ton of things I have installed in this 32GB, 600Mhz processor, is just insane! I would love to buy a revamped version, with modern chips and 512GB... I would conquer the world with it!
But, unfortunately for us, I think this kind of openness is and will continue to be a no-more. Yes, companies want us to pour our money in their exclusive ecosystem, but that's a security question here which have to be remembered: I use my Note10+ to pay things, with Samsung Pay. There's no way to maintain this kind of feature without Knox and a more closed OS, unfortunately. In the other hand, even with all this obstacles and security measures literally millions of people still manages to install virus and malwares in their devices. Just imagine what would these people do with a totally open device? And, when things goes worse, who these kind of human being would sue?
So, unfortunately there's a logic in motion here, and still more unfortunately we are a tiny minority nowadays. Samsung certainly wouldn't make profit with us being sued by millions of dumb people at same time. That's a true problem. So, maybe one day we'll find some kind of Indiegogo campaign with a revamped N900 version being sold, and I still doubt such project would be able to earn the necessary funds to become real. But, normal devices sold in normal stores for normal people? Unfortunately, that ones will be more and more closed in the foreseeable future.