"I know ARM people who think that x86 is an "ugly"
architecture. But the fact is, of all the architectures out there, ARM
right now is the ugliest BY FAR.
While PC architecture (including not limited to the x86 processor) is ugly it is at least a common platform. One PC will be much like any other PC. There is a baseline of hardware that can be expected to exist at well-known locations and hardware beyond that is on an enumeratable bus structure with the registers needed to enumerate the root bus in a well-known location.
The arm world isn't like that. The processor architecture itself is somewhat cleaner than x86 though it does have it's own share of ugly hacks but the platforms surrounding it are a total mess. There is no baseline selection of hardware, everyone puts the key hardware in totally different places, hardware vendors (sometimes) document how to use the hardware but don't document whose IP block they used making it harder to work out where drivers can be shared between different vendors hardware and enumeratable buses are the exception not the rule.
The result of this is that to install debian on a PC I grab a debian CD and install it. After installing it I am running a debian supplied kernel which I can be reasonablly assured will be kept up to date with security fixes.
To install debian on an arm box I google for instructions specific to that box (without internet I would be screwed). Often these instructions lead to having a system with customisations I don't want and have to undo or live with. Often I will end up running a vendor kernel which will often be somewhat out of date and is unlikely to get security updates in a timely manner.
Things ARE improving, multiplatform and device tree are allowing debian kernels to run on more arm hardware but even on the hardware it does run on lack of support for some features (graphics is often a source of trouble) is a common problem.