The rumor that Microsoft is building a version of Windows 10 that can only install apps from the Windows Store has drawn criticism before it's even official. Epic Games founder Tim Sweeney took to Twitter to attack the operating system. Although its real name is named Windows 10 Cloud, he's dubbing it "Windows 10 Crush Steam Edition."

Sweeney is convinced that Microsoft wants to exercise total control over the Windows platform and destroy Valve's Steam. Last year, Sweeney attacked the Universal Windows Platform API. He claimed (incorrectly) that third-party stores such as Steam would be unable to sell and distribute UWP games, leaving them at a disadvantage relative to Microsoft's own store. He followed this statement with the claim that Microsoft would systematically modify Windows so as to make Steam work worse and worse, such that gamers grow tired of it and switch to the Windows Store.

A version of Windows 10 that can only use software from the Windows Store, as Windows 10 Cloud is believed to be, would certainly be bad news for Steam. Steam can't be found in the Windows Store, and, due to the way it works, it's unlikely that it ever will be.

But Sweeney's concern nonetheless feels misplaced. While this is, of course, all rumor at the moment and Microsoft's plans could be something else entirely, the current belief is that Windows 10 Cloud will be aimed at markets where Chromebooks are making inroads, in particular education. Chromebooks appeals to this space for many reasons, but one of its biggest advantages is that Chromebooks aren't PCs and aren't a platform that supports the installation of arbitrary software (whether it be game software or anything else). This makes Chromebooks very robust, with little risk of malware or other undesirable software.

In this context, Windows 10's ability to install Steam or any other traditional Windows application isn't a feature. It's a liability. A version of Windows 10 that's restricted to a browser and a sandboxed, tightly restricted Store applications, solves this liability.

Moreover, Chromebooks do this all by default. Many schools do not have substantial IT resources on hand, and they certainly don't have the infrastructure to support a bunch of domain-joined Windows 10 PCs, all with a carefully configured locked-down environment. They need systems that offer this kind of security by default, along with simple cloud-based user and device management.

@alexstamos @BrendanEich It's great for Microsoft to compete with ChromeOS, but NOT BY LOCKING OUT COMPETING WINDOWS SOFTWARE STORES. — Tim Sweeney (@TimSweeneyEpic) January 31, 2017

In his tweets, Sweeney recognizes that Microsoft wants to compete with Chrome OS. But he fails to understand what the company must do to actually offer that competition. He wrote that "it's great for Microsoft to compete with ChromeOS, but NOT BY LOCKING OUT COMPETING WINDOWS SOFTWARE STORES." This statement represents a failure to understand that "locking out competing Windows software stores" is, for this market, positively desirable. It's fundamental to preventing the hard-to-support free-for-all that a Windows system would otherwise represent.

Windows 10 has great admin features to limit user software installs. They don't need to lock out competitiors to achieve security. — Tim Sweeney (@TimSweeneyEpic) January 31, 2017

A later tweet does recognize the value of this lockdown, but Sweeney says that Windows 10's "great admin features to limit user software installs" should be used instead. This again suggests a misunderstanding of the target market: systems will be used with little to no supervision and with little to no administrative oversight. To compete against the Chromebook, Windows 10 Cloud needs to be locked down by default, and it must not offer any ready way to disable that lockdown.

In his complaints, Sweeney also fails to consider what happens should the Chromebook threat go unaddressed: Chromebooks running Chrome OS will proliferate. These machines will not support third-party stores, they will not support Steam, and they will not support PC games at all. Sweeney may not want Microsoft to build this world, but even if Microsoft doesn't create it, Google already is doing so.

Decades of poor quality software that's rife with insecurity and instability is in no small part responsible for the consumer appeal of sandboxed, locked-down platforms. They offer an escape from many of the problems that plague PC software. Like many champions of the PC, and particularly PC gaming, Sweeney is willing to tolerate these hardships in return for an open platform that offers few limitations on what kind of software can be written, or by who. The success of iOS, Android, and Chrome OS has made it inescapably clear that many computer users would rather have safety and predictability instead. Microsoft has, perhaps belatedly, realized this demand exists and is building Windows to address the needs of the full range of its userbase. Sweeney, it appears, would prefer that some segments simply go unanswered.