It's not that there's one or two blockers that just need to get cleared out of the way. It's that ARM desktop PCs don't have solid momentum and commitment.

When Apple announced they were moving to ARM, it was "this is happening and everyone needs to get on board or they're going to be left behind." Microsoft has ARM support in Windows including an x86 translation layer, but there's certainly no "get on board or you'll be left behind" ultimatum. Microsoft intends to keep supporting x86 and in fact x86 will continue to be the premier platform for Windows. That leaves desktop ARM without momentum.

Some things in the world are about momentum and the commitments people are willing to make given the commitments of others. Every Mac developer knew that time invested in porting to ARM would pay off. Apple was committed to ARM. They'd spent a decade making their own chips. They weren't just going to abandon ARM a few years later. Developers knew that competing developers would port to Mac-ARM so they had to make that commitment as well. Developers knew that Mac buyers were going to be clamoring for the Mac-ARM machines.

Does Microsoft care about Windows on ARM? Do Windows Developers? Do PC buyers? The answer to all three seems to be "no" (or at best "eh, a bit"). Given that no one is committing to Windows-ARM, everyone just takes a wait-and-see approach. Without the commitment and direction, others don't want to make those commitments. Would you buy an ARM PC knowing that everything will likely need to run through translation layers? Knowing that Microsoft's support for ARM doesn't even extend to flagship products like Visual Studio? Knowing that so many third-party devs won't see enough ARM users to justify the port? And if you're not going to commit to ARM, why should anyone else in the ecosystem.

Apple solved that indecision/commitment issue by 1) saying unreservedly that it was moving to ARM and would be leaving Intel entirely; 2) offering chips that didn't just match Intel performance, but solidly beat it offering users a huge reason to want those new machines fast.

Microsoft doesn't have either of those and Intel is making huge strides. They've released big-little architecture chips and started improving performance a lot. They're likely to start closing the gap on chip process either by renting TSMC or improving in-house fabs. Plus, "desktop" PC users (rather than laptop) often don't care about heat and form factor like Apple does - they aren't looking for a Mac mini or Mac Studio. They're happy with a tower that they can stick a giant graphics card in and that can accommodate a 100W CPU.

Beyond the issue of commitment, as others have pointed out, Apple is just farther ahead on ARM performance than anyone else. Qualcomm is trying to make their own custom chips to improve performance, but right now Intel has better performance and Intel seems recommitted to maintaining their performance advantage (against non-Apple chips and at least wants to bluster about beating Apple).

Given this environment, it's hard to be the one willing to invest the money to break the logjam. Maybe Qualcomm will if it can leverage its investment in mobile CPUs for desktops. However, it's hard for a chip startup to want to take on Intel when users, developers, and Microsoft aren't enthusiastic about Windows-ARM. It's hard for a user to want an ARM PC when performance isn't dramatically better, developers don't care, etc. It's hard for developers to care without users caring. But I don't think even Qualcomm can break the logjam. I think they like their margins too high to want to price their chips at a level that might see people clamoring for their processors and I think Intel's 12th-gen (and successive generation) chips will make it hard to beat them on performance.

Apple just controlled enough of the ecosystem to offer the amount of commitment necessary - and is a company that doesn't mind telling users to leave their comfort area. Microsoft likes to tell users "don't worry, that program from 1995 will still run" and in some ways that's awesome. A 1995 Mac program wouldn't work multiple times over (when Mac OS X eliminated Classic support, when Apple moved to Intel, when Apple eliminated Carbon, when Apple eliminated 32-bit support, and when Apple moved to ARM). Some of those had translation layers, but some didn't (and often the translation layers died along the way).

The blocker is that no one is committed to Windows-ARM and Desktop-Linux-ARM. I can't even download an Ubuntu desktop ISO for ARM. I have to download the server version and then install the desktop. Without someone standing up and saying "this will be the way forward even if it is uncomfortable and the past will be left behind" it's hard to get people to move.

To put it another way, when Google shows a lack of commitment to things, it means we inevitably see comments here saying "it'll be killed in 2 years." I'm not accusing Microsoft of abandoning anything, but it does feel like Windows-ARM isn't likely to get traction and while they might keep it alive, they probably aren't going to continue to invest the money to really make it thrive beyond what is already offered (which isn't bad). However, the lack of a coordinated direction between Microsoft, developers, and users means that there isn't momentum in that direction. No one wants to waste their money on Windows-ARM.