Given that the kernel still identifies as 3.0.101, my guess is that they just backported some features from 4.x and applied them to the ancient kernel ;-) I am not so sure that qualifies as a 4.1 in terms of Android support.
I think the discussion about which devices live longer is simple to answer: Apple (iPhone) and Google (Nexus/Pixel) do probably the best job of supporting their devices for a while from a manufacturers point of view (in comparison to Samsung, Xiaomi, LG, Huawei, Sony, etc.). However, if you want to spend some time and flash alternative ROMs yourself you are better off with Android due to the large modder community, but it also depends a bit on the device you bought.
My biggest issue on the other hand, is that if the manufacturers would also open source the drivers, they could be included in the Linux kernel and we would not have this discussions, because one could simply use an up-to-date kernel as you can with every PC.
And how does the kernel affect you in any way. Most of the internet runs on old kernels because servers user long term stable kernels anyway. If they ux is good the kernel shouldn't be a problem to you
1. UX: most of the time kernel updates don't affect the user experience. However, from time to time there are scheduler updates which can have positive effects.
2. Security: Being able to run the kernel with the latest security updates is evidently very important to have a system that is not vulnerable to newly discovered exploits.
3. Dependencies: As discussed already, some software components like the Android itself requires certain kernel features and therefore certain versions to let you run the latest versions of the software.
Btw. even LTS kernels are just supported for six years or so.
My biggest problem with the situation is, that 99% of the software is open source (Android incl. the Linux kernel) and just a few vendor-specific drivers make it very hard to upgrade the kernel and therefore the system.
I think the discussion about which devices live longer is simple to answer: Apple (iPhone) and Google (Nexus/Pixel) do probably the best job of supporting their devices for a while from a manufacturers point of view (in comparison to Samsung, Xiaomi, LG, Huawei, Sony, etc.). However, if you want to spend some time and flash alternative ROMs yourself you are better off with Android due to the large modder community, but it also depends a bit on the device you bought.
My biggest issue on the other hand, is that if the manufacturers would also open source the drivers, they could be included in the Linux kernel and we would not have this discussions, because one could simply use an up-to-date kernel as you can with every PC.