"Flagship" Alienware Steam-Machine – NO upgrades – Bad thing

As you might know Valve and Alienware have been working together to provide the so-called "Flagship" Steam-Machine, which is supposed to lead the Steam-Machine trek.

my video version is here:

Gabe Newell gets quoted on the Alienware title website:
"The result of our collaboration is the Alienware Steam Machine, a console that encapsulates the full potential of what a Steam Machine should be."

NOT upgradeable - ??? FULL Potential ???

For me that Machine definitely doesn’t "encapsulate the full potential of what a Steam-Machine should be." I doesn’t even reach half of the potential a Steam-Machine should be.
A Flagship device should be fully UPGRADEABLE.

Why has Valve been mentioning this since the first announcements in September – UPGRADEABILITY. They wrote they create a guide for helping with upgrade decisions.
And now the "FLAGSHIP" Steam-Machine is not upgradeable - LAME.

I won’t buy that Steam-Machine, I’ll buy that CyberpowerPC Steam-Machine. It’s fully upgradeable with standard PC components. So I don’t have to buy a whole new Steam-Machine for being able to play 4k resolution fluently in three years, I’ll just need a 250 Dollar new graphics card and put it into the case.

So you buy the Alienware Steam-Machine and cannot upgrade, big deal, just buy a PS4 or an Xbox One, also no upgrades. The only difference between that Machine and the traditional consoles is that you’re not forced to keep SteamOS on it. But that’s all.
Very disappointing for a "FLAGSHIP" Steam-Machine which actually should provide all main advantages of a Steam-Machine not being a 100% traditional console. Why do they close down that leader Machine by using a proprietary tech solution just like Sony and Microsoft. I wouldn’t have cared if it was a Machine from some of the PC builders, but not the main "flagship" device - that’s ridiculous.

What I’m interested in is what others think about the non-upgradeability of four of the Steam-Machines and especially the "flagship" one:

Is it also an obligatory feature a Steam-Machine should offer for you?
Do you don’t care at all if upgrading is possible or not?
Do you accept the trade-off between the small form factor and using minimized tech solutions?
Is it Ok for you to buy a complete new Steam-Machine after only 3 years just to have a bit performance gain?

Last but not least: If some Valve staff actually read that stuff here, here’s a hint:

Make a second "flagship" Steam-Machine, same design as the Beta-Prototype and fully upgradeable – and you can shut up and take my money And I would rather give my money to Valve than to CyberpowerPC. I’m from Europe and I don’t know that company, but I’ve been supporting Steam and Valve for years. Please give me the possibility to give YOU my money and not to CyperpowerPC with a fully upgradeable Machine.

Technical Note: Minimized custom printed circuit boards, like in notebooks and tablets, can only be upgraded "theoretically", but not for a regular end consumer. Reason: the CPU, RAM and graphics solutions are not available for end consumer retail. You have to buy a complete new device if you want other hardware.