Canonical offers free Ubuntu Advantage for 3 machines which gives you extended service maintenance for even older distros like 14.04 (which is what I am using to type this). Ubuntu is a great distro because it supports each LTS for a full 10 years. Constantly upgrading and breaking things and having to switch software and workflows is way more insecure imo.

Additionally, there are tons of devices out there that will never get updated that run even older unsupported linux distros and do their job just fine. And modern written bash will run just fine there too.