Heres my opinion on this subject

1)Alot jobs has gone through too much of oversimplification.i wont list all of them but the biggest offenders are mainly healers and tanks , with the former losing the absolute minimum of what could be considered a dps rotation, And the later losing a whole system that interacted with other jobs the aggro system. Tanks have also be given alot of abilities that fit not a similiar role but the exact same role, for example plds and gnb aoe dot, Drk getting War inner release. Ill also include as minor offenders, War and gnb sharing the same 15% cooldown and Drk sharing the same aoe mitigation with gnb. With the exception of Gnb who was tailored to fit this expansion ,
pld lost the least having the least interaction with stances ,
Drk has been the second most affected , losing alot of spells and situational pros each stance gave mitigated alot by being reworked,
War has been affected the worst but is somewhat remedied by the fact that the new lvl caps was used to reintroduce some of the strength he lost. For example the extra healing of tankstance was given to thrill , inner beast has been given in the form of raw intuition rework , and his heal given via nascent flash.
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The healers Simplification has been mostly allocated to the dps abilities but do to the abudant choices for healing healers have this has reduced them to be in a state of Whm but with
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2)Tieing to the first comment This simplification has done nothing to help the myriads of new players shadowbringers introduced ,something worsened by the option to simply skip everything. There is still not a decent tutorial to help players out and eu specificly the auto translate function is too bad to do the job is supposed to do. This in coordination with the fact that when people gather fights are inevitable , as well as the discouragement of putting in helpfull tools that would be able to help people improve (ironically to avoid the second thing) has made it so that most people can play for hours on end and never actually improve. Adding to that the strict tos has made every arguement that this situation can induce be solvable only by leaving, reporting or avoiding it all together. This does not promote a healthy atmosphere, and can be easily abused.
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3)More info about job direction. In here i will list the biggest offender summoner, This job has been reworked since i started playing in late HW 4 times however the 5.0 was the most questionable set of changes ive seen. It changed the job systems in a way that ended up in the complete antithesis of the old system. from fluid to rigid this made the few words they have said about why they did them contradictory. Even though 5.1 and 4.1 changes were easily understandable the 5.0 weren't. So ye pls talk to us more often Devs TT.
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4) The game needs an upgrade. Ill go to the extreme and say that with all those problems happening and the fact that currently with 5700xt and 3600x ryzen series i can go down to 50 fps from 144 in limsa while in a game like doom eternal i can reach 2000 , id w8 5 years just so that this game could be remade or change engines or get whatever it needs. Hopefully we will see an upgrade with ps5 version.

Thats all i can think on the top of my head.