You mean the price paid for stable kernel ABIs, so proprietary drivers can use them? The Linux kernel is the most safe operating system component to upgrade, m

You mean the price paid for stable kernel ABIs, so proprietary drivers can use them? The Linux kernel is the most safe operating system component to upgrade, mostly because the Linux kernel people care deeply about compatibility and not breaking user space. While it is still not free to upgrade, the cost is minimal compared to the cost (in real money, risk, security) of backporting major components to older kernels, like Red Hat is doing. Red Hat is maintaining old kernels for having a stable kernel ABI (among some other reasons), not for general "stability". Personally I run only CentOS, but always with a recent kernel, albeit usually a LTS one. Mostly to get exactly these type of features described in this article.