These are all variations of the Linux kernel, as in they are compiled with different options or components. In this case we’re talking about different schedulers, which is the part of the kernel which decides what tasks are executed, when and for how long, etc.

I guess you’re getting to the point in security where you really should consider the cost/benefit of safety vs convenience. Do you really want or need to have an immutable system? While there’s obviously an argument to be made about the security benefits on those distros, I’d say that they’re mainly made for CI/CD, cloud environments etc, and probably not something you want to put in a laptop and use as a daily driver. Your laptop is likely already more secure than 99% of other laptops, and in the end all you need to not get malware are a firewall and common sense if you’re not an exposed entity.