Aren’t Kernel versions tied to device model for Synology? My DS918+ returns “4.4.180+” as its kernel version. That’s pretty.. old?

Do/can they downstream some of the changes without changing the Kernel version?

Unlikely, I am on DSM 7.1 and it is 4.4.180+, although I know heavily patched. I have read DSM 7.2 will land 5.10.

I don't think Synology ever update their kernel with DSM. So the kernel you get when you buy it will be the one that last for its life time.

But I do hope there will be model, especially entry model that comes with 5.10.

Synology's Linux timeline is simply too slow.

They might update their kernel, just not the kernel version. They seem to be using SoCs in their devices and then respective BSPs by the SoC vendor, which are notorious for not being updated for a new kernel.

I have one of the infamous Atom C2538-based Synology there, and it is running kernel 3.10.108, built in october 2022. The device is 2019 model (the SoC was introduced in 2013).