If you enjoy RDM, keep playing the job. The balance with RDM has always gone up and down every expac so it will surely get back to middle of the pack at some point. I've played it since it was introduced in Stormblood and I've continued to play it through all its ups and downs. With MMOs it's important to remember that a job normally won't stay in a bad place forever so I wouldn't avoid a job just because it's not currently doing great. And people are still playing it and using it in end game content, it was actually the most desired caster for the latest ultimate when that ultimate first dropped. (when I was looking for a DSR group I put that I could play NIN or RDM, every single group wanted me on RDM) It's also still being used about as much as BLM in this savage tier, SMN is only significantly above the 2 other casters in representation because it's the one caster that's punished the least for moving a lot.

And fortunately at this point in the tier gear can make up for jobs that are under performing. So unless your plan was to do speed clears or something, RDM will still be able to clear the content. This tier was just a weird one because the dps check for the door boss was unusually tight compared to previous tiers. I don't see that situation happening again any time soon. Obviously I don't think RDM is in a great place, but it's also not worth giving up on a job you like because it's in a rough patch atm.