Why can't we have jobs with this level of depth and customization in FFXIV?

[Risvertasashi]

Devs already said if they have a job that focuses more on the pets in fights, it is a unfair disadvantage compared to others. In this game at least. FFXI goes at a pace where you can afford to mess with things like managing your puppet/summon.

How about a similar level of customization on the player, then?

Lets like at the high end game event in current FFXI delve. The following jobs people take in this 18 man event.

Job - Role
MNK - DPS/Tank
DRK - DPS
DRG - Argon (-25% defense) / dps (low dps but hey they mainly for argon)
WHM - Healer
SCH - Healer/buffer
BRD - buffer
COR - buffer
GEO - buffer/debuffer

For a game that has 22 jobs basically people only take these few around to endgame. If you have a non standard group of friends sure you can take non optimal jobs but any pug they will only want these certain jobs.

You see jobs that you could customize to do a role like pup where never taken or used in endgame because there were specialized jobs that did their role better.

Sure, but I'm not advocating we copy FFXI endgame, mechanics, or puppetmaster.

You're basically asking for what an earlier poster pointed out: you want multiple builds and for them all to be viable. Which yeah, would be awesome, but how often do you see that? Yeah..

If you look at my previous posts, you'll see I'm not asking for that. I'm OK with a lot of nonviable builds as long as 1. a few of them are viable. Even 2 or 3 would be better than what we have now and 2. gives us something to tinker with when not in high end raid content and maybe losing that 10% efficiency doesn't actually matter that much.