Are jobs bound by lore?

[Vyrerus]

If you been around as long as I have...

Conjurer had Protect and Stoneskin until Heavensward and a job trait called, "Proshell" that gave Protect cast by a Conjurer or WHM Magic Defense as well as physical. So it had a whopping 2. It was rolled into Protect itself in Heavensward, so that SCH and AST could also reapply Protect without requiring a WHM for the best Raid defense. Comparing CNJ to other classes and talking about supportive barriers is kinda silly, since it's the only class that is actually a full on healer, required by every healer for cross class until Stormblood.

Arcanist also had two damage reducing abilities. One was the barrier that inflicted a dmg down debuff, Eye for an Eye, and the other was Virus (with Supervirus perk it lowered all forms of damage via lowering STR DEX INT and MND of the mob).

Once the two became jobs, SCH had more barriers. They pretty much have to default to saying that Geomancy is similar to Conjury/Sharlayan Astro, because it's the baseline healing techniques known to them(Nymian technique are a lost art). The Geomancy barriers they're referencing are on full display in Swallow's Compass as literal barriers to progression.

It's sure gonna get awkward in Endwalkers when AST no longer focuses on barriers either lol.