I am quite willing to concede that Apple doesn't need to lock the bootloader on the Apple Silicon Macs, as long as no viable alternate OSes for it emerges and / or every reverse engineering effort to port and run alternate Oses on it can be countered and hampered by changing the hardware in the next model. So in effect, Apple can continue claiming that Apple Silicons are "open". But how much does this "openness" of Apple Silicon matter when they are only available in custom hardware (the Mac platform) and any change in the hardware means you may not be able to run the OS to use the Apple Silicon CPU / SoC to the full extent? The soldered parts ensure planned obsolescense and limited life anyway for every Apple Silicon Mac. So even if someone manages to reverse engineer one model, it will have a short life, and they will have their work cut out for the next new Apple Silicon with enough hardware modifications to sabotage any serious competing OS.

If Apple really wants it users to believe that Apple Silicon Macs are open, all it has to do is release the drivers for an alternate OS. For all those who claim that it will be an additional unnecessary burden, remember that Apple has done it in the past with Bootcamp and Windows driver. For those who claim that Microsoft cannot offer Windows on Apple Silicon because of their tie-up / contract with Qualcomm, note that there are other alternate OSes too. If Apple doesn't want to release their hardware literature to the public and is comfortable with only working with corporate I can point Apple to IBM or Canonical who make Red Hat Linux / Fedora and Ubuntu OS respectively, and who don't care about including propreitary driver blobs in their distribution (as far as I know).

You can definitely claim that these are measures that Apple has taken to harden the "security" of the Macs - a hardware that cannot be modified and system software that cannot be easily replaced does add to a device's security. But from that perspective, an open bootloader is clearly a security threat too. When Apple locks the bootloaders on the Mac tomorrow, and claims it is to make the device more "secure" it would be true! But then, why stop there - now that the system software is "secure" from tampering, why not also extend this "security" to other softwares that will be run on the Mac? The "secure" solution is obvious - allow the softwares to be only be installed from the Apple App Store. Now the Mac is as "secure" as your iPhones and iPads!

Are you claiming this won't happen - that Macs will never be locked down machines like the iDevices? What indications have Apple given that suggests this? (Remember, they have already taken away our ability to customise or repair the hardware, and crippled our ability to run the software we want on it).

> I think if they were going to lock it down, the ARM transition was the perfect opportunity.

No, the amount of bad PR it would have generated would have tarnished the Apple Silicon branding, and all the polarised debates and the negativity it would have generated would have taken away focus from the good features of the SoC. It would definitely have reduced the sales of the M1 Mac devices, and that would have made the shareholders jittery too. Let's not forget that Apple (and others) who want to push such locked down systems in the personal and professional computing field face an uphill task to change consumer behaviour - we consumers are used to, and expect to be allowed to tinker with our hardware and software. Apple (and others) obviously cannot change that expectation overnight, and hence the slow phased approach of eroding our consumer rights and computing freedom is the only way to achieve their goal.