The FFXIV team also isn't a monolith, nor are decisions made lightly or in a vacuum. I wanted to give a little context. For background, I'm a developer who has worked in both consumer-facing products and for a Japanese company, though I'm not in either on at the moment.

You'll likely have a community team or teams that read forums and get a general sense of the sentiment and compile that feedback giving it back to someone in product development and design. It's going to be highly compressed because it has to be because of time constraints. Designers are busy doing design and don't have hours upon hours to read the forums.

Designers will likely have a head of design. There may be a hierarchy of leadership, but I would imagine there's less than a dozen job designers on staff. Design, product and technical leadership will determine the broad strokes of where they want the product to go. These conversations will have been over months or years to arrive at their current strategy. Roadmaps will have been created from these strategic goals.

Product Managers/Owners (orgs have different names) will be responsible for what work is prioritized on the dev side in coordination with other departments. You can't code up new job abilities without designs and assets, though placeholders will often be used.

The person who designs the job probably plays it but not extensively. The design skillset and the player skillset are different but overlapping skillsets. Remember the designer has to work from theory a lot of the time because the job as imagined doesn't exist yet and experimentation is slow.

Once the job is in a playable state, testers will test it and the designer may play around with it. Testers will mostly be looking for bugs, though. The developers who coded up the new abilities may give initial feedback to it feeling clunky, but they might even play the game.

Between when the job design and coding, it may be months before the design sees something actually playable. The exception is potency changes and deletions as neither requires coding or asset creation. Both can be tweaked with metadata changes alone, and likely have a much faster turnaround time. The exception to the exception would be quest-given abilities.

In order to make significant job adjustments, it's going to take weeks to months depending on how many dependencies are created in terms of assets, coding, etc. E.g., removing Kaiten may have been something they wanted to do for a while, but replacing it with something else would take a long time.

Between the feedback process and the implementation of something new is multiple people, months of effort, and shifting priorities. It's not uncommon for something extremely important to get lost in all that. And SE isn't alone in that. Just because there's not instant turnaround doesn't mean feedback isn't being listened to. Sometimes it just needs to work itself through the system.