[janm]

I disagree with both these points:

In some cases old, actively maintained code is more reliable. However, I have seen many cases where old, actively maintained code (depending highly on the quality of the maintainers) has lost reliability because the original principles of the codebase have been lost.

Device drivers (especially in multiprocessor systems) have very many unpredictable paths. In my experiences in writing devices drivers and GUI code code (as well as lots of code in the middle), device drivers are more likely to have the unforeseen codepath. With GUI code, you can constrain concurrency so that possible codepaths are also reduced.