To me there is alot of jobs that play extremely similarly and other jobs that have the same feeling flow to them that they feel rather repetitive. Jobs don’t have to be 1 to 1 copies to feel extremely similar to each other especially when they have overarching themes that make them feel similar
Let’s use some examples
SGE and SCH is arguably the most egregious example in the game. They have the same DPS rotation in both AOE and single target (they don’t have one), addersgall is a near 1 to 1 copy of aetherflow just as kardia is a near 1 to 1 copy of embrace. Soteria and union, physis and whispering dawn, even their GCD shields have exactly the same shield potency by design. Energy drain is really the one great distinguisher and it’s not remotely enough
Beyond that specific example all the healers play extremely similarly. 11111111 oGCD spam (lilys aren’t a “noticeable difference” on this front). The tanks are basically 2 tanks. There is the 1-2-3 to build some gauge to use a big attack every now and then and then a button you press that allows you to just spam that big attack (WAR and DRK) and then there is the 1-2-3 gives you access to a proverbial 4 and another “combo” with a burst window that relies on that combo (PLD and GNB). On the DPS front MCH and RPR are incredibly similar (rigid 1-2-3 with 2 gauges both of which are integral to the burst and the burst is spammy), NIN and DNC feel very similar to me (which incredibly overfull burst that you stockpile minutes in advance with their core mechanic being short snappy stored DPS that’s refunded later in dance steps and ninjutsu (also note PIC seems likely to fall into this category as well)). SMN feels like a healer without heals. MNK, DRG and SAM share the branching rotation motif that while not the entirety of their rotation definitely feels like a similar foundation that I notice when swapping between them
It really feels like BRD, BLM and RDM are the only ones that feel unique and even they share a lot of features with other classes you pick up on (RDM has the “gain 50 gauge to immediately enter your burst button, BLM has the bloodfest style “press to receive big damage gauge related button” in amplifier and BRD has both the same generic 20% self buff and 6% party buff that feels similar to the melees)
Of course with this many buttons on this many jobs it’s hard to make no overlap but I feel almost every job I can 80% understand it as long as I’ve played one of its partner jobs and that’s a problem