Yeah it's about support contracts, which covers a lot of services actually such as maintaining security audited package repositories. But most importantly it's about support life cycles you can rely on for a long term investment of time and infrastructure outlays.

For example, RHEL 10 has a planned support phase out until 2035, with extended support available until 2038.

They do tend to have a different goal for their intial installation and configuration to consumer distros, with a focus on security and providing tools you will need in an enterprise hosting environment.

> For example, RHEL 10 has a planned support phase out until 2035, with extended support available until 2038.

I wonder if that's 19 Jan 2038. https://en.wikipedia.org/wiki/Year_2038_problem

RHEL 10 lacks 32-bit x86 packages, so it goes past that date. RHEL 9 support ends before that date.

Support, especially for older releases (which is important for heavily regulated companies that can't upgrade on a dime).

More heavily vetted (i.e. older) kernel and support for every package in their repository.

Guaranteed security hotfixes with some time guarantees.

Training and certification programs.

SLAs, support, LTS services etc...

If you have more than a 100 linux machines you certainly need someone who knows linux to support them. You can either hire a team to do this or hire someone who will manage a support contract with suse/ubuntu/red hat etc.