I’m not sure why Astrologian needs a gap closer? Like what would purpose would it serve?

Sage has theirs for rapid repositioning to use its melee range attack (Phlegma), White Mages again is likely for rapid repositioning before Cure III / Holy.
Astrologian doesn’t have any abilities it would justifiably have a gap closer for? I mean, the reasons Sage/White Mage have them are flimsy enough.

As for dying because your job didn’t have a gap closer, I know the devs can be bad at balancing but even I don’t think they’re that bad lol. There is no content in this game that cannot be done without a gap closer, otherwise Scholars, Machinists and the few other jobs without gap closers (if there even are any) would be completely unusable in said content.

I died a bunch as Scholar on the first boss of the level 99 dungeon. I even went in with trusts and managed to get killed a bunch of times lol, they practically give you the answers. There’s nothing wrong or shameful with not being able to immediately do something the first time you encounter it. Just keep trying and eventually you will get it; asking for abilities that do the job for you isn’t going to help in the long-run