I think looking at lights is actually a very good way to see how DIR may handle equipment change due to new technology (since the HID/LED industries are moving forward at a pretty steady pace).
For backup lights, I think the tried and true DIR standard is for a simple tube-style light with a twist-on head that doesn't activate with pressure, 3 C-cells in series, and a bolt snap attachment at the end. There are various reasons for these requirements, not least of which is reliability (not overdriving the halogen bulbs which were common at the time). Now, you've got LED backup lights which have nearly bulletproof emitters with thousands of hours of useful life, can run for over a day on fewer/smaller batteries, with no overdriving issues. Are these DIR? Eh, hard to say. Even Halcyon makes a 2-cell mini Scout LED, after all.
Some hardcore adherents will still use no less than their dependable 3-cell halogen scouts, photon torpedos and rats. A lot of people now use smaller LED backups, even in caves. I think most of the focus nowadays is on having sturdy construction with a twist-on mechanism and bolt-snap attachment point. The details may slowly change based on what "everone" is doing, but the concept of reliability, standardized deploy/stow procedures, etc. will remain.
That's part of the reason why it doesn't really matter what some shop may say to bamboozle a customer. If you don't know what DIR is, you're not going to seek out a DIR bible to verify the claims, and if you do know DIR, you're not going to rely on a starburst sticker emblazoned with "NOW DIR-COMPLIANT!!" stuck to a blister pack.