purposefully. they dont want you messing with their device. its that simple.

GrapheneOS is a really easy process, hardest part is unlocking the bootloader (which isn’t hard at all).

Rest of the process is just clicking 3* buttons on a website and you’re done.

*Some buttons you have to click multiple times

For many reasonable vendors, this process is very unlikely to brick your phone, and requires minimal effort to unlock the bootloader or load/change the recovery.

However, many phone vendors (Xiaomi was the one example I know) subsidize phone price with data surveillance and ads; so they don’t want users to use other OS, as it hurts their revenue.

There are a lot of reasons here which are correct, but one huge Factor when I was working with custom roms was the fact that the actual underlying hardware driver and firmware were a black box. Generally speaking you would need to harvest the binary files that made things like the camera, gps, and/or touchscreen work. Sometimes it wasnt too hard if you were going from one android skin to another that used the same underlining operating system, but if you wanted to make serious changes, and the phone manufacturer wasn’t great at sharing, it could take a very long time to figure out what data needed to be passed to the camera to make it turn on and be available to use. What got even worse is if you wanted to upgrade your android version (5 to 6 lets say), where android made serious changes under the hood, you ran the risk of having these blobs not even work with the system. They would expect something that android no longer passed or provided. Or they were using some deprecated API to make their function a accessable. It just became impossible to do without being able to recompile the binary only portions that weren’t subject to the gpl. As android has gotten more security conscious it has made things even more complicated.

GrapheneOS is a very easy install and can be done simply by plugging your phone in and clicking some buttons on the browser.

Most OEMs make this intentionally difficult. Partly for security and stability reasons but also because that device is likely feeding them data and pestering you with ads, and that makes them money, which is really all that matters at the end of the day.

The web-based installer for GrapheneOS is very easy to use. The catch is that it only works for Pixel phones (and only those that are still receiving updates).

https://grapheneos.org/install/web

It used to be easy… When people were actually making custom ROMs for everything and you could literally just plug the device into your PC and run a program to do everything. I don’t think there is anything inherently in most phones stopping this; it’s the lack of people developing custom stuff for every piece of hardware out there. Some phones do actively try and thwart custom ROMs, such as Samsung with their Knox bullshit, but most don’t need to; nobody is hacking them in the first place.

Xiaomi becomes a pain in the ass with HyperOS. It’s sad. The hardware was good and you could install custom roms.

Less tinfoil in my take: a good reason there doesn’t exist other OSs is a lack of drivers and support for hardware. Good luck getting your screen to work if it’s proprietary to the manufacturer and device. Can’t communicate with the ASICs if they don’t use standard protocols, etc.

This was a big issue back when I was involved in the LG G Flex 2 community and I can assume it only got worse since then.

PCs are a bit different IMO since generic drivers might get you pretty far. Even then, support for modern graphics cards (for example) would be near impossible without the manufacturers playing nice or in-depth insider knowledge

Unlock bootloader (depending on vendor, you have to do an online verification),

A few years ago, there were huge issues with reseller unlocking the bootloader to inject ads on the phones they sold, which forced many android phone manufacturers to add online verification with long wait time to prevent bulk unlock.

Because vendors realized they’ve made a mistake. They’ve lost control they can’t regain. Same thing with game consoles.

So, it’s actually a feature for the companies selling you phones.

Look up the history of how Android was developed, particularly what happened when Google took control, and you will find your answer. Ofc if you want to help, feel free to be the change that you want to see in the world, I’m only talking here about the past, as you asked about.

TLDR version of that history: greedy corporations surprised everyone, somehow, by ultimately acting in a greedy manner. B-b-but their slogan was “Don’t be evil”! - once upon a time. And ofc Apple sure as hell wasn’t going to cooperate with that “nonsense” of allowing anyone to take even one step outside of their walled garden. So what then is left to us, besides what you see before you?

I honestly don’t think I’ve ever heard an average user say: ‘I like my phone’s hardware, I just wish it had a different OS.’

Phones by and large are seen as a locked system: you specifically choose to buy Android or iOS and stick with that.

There’s really no incentive for companies to make different OS installs easy. I’d say there’s plenty of reasons not to: do you really want to give the average user that much power to fuck up their phone? I assume there’s also some security implications if they made it too easy to fiddle with.

So yeah, it’s difficult because you’re fiddling with something that wasn’t meant to be an end-user thing in the first place.

Don’t get me wrong, I’d love it if they made phones much more open in terms of hardware and software, but the big guys aren’t going to do it.

GrapheneOS’s guided installation is simple enough anyone should be able to install it IMO.

I can’t answer your question, but is quite unfortunate. It really shortens the lifespan of many phones as they stop receiving OS and security updates after awhile (and in many cases, right away).