Actually, this amount of time is normal for Square Enix. Took them 2 or 3 years to remaster FFX, took Naughty Dog at most one year (probably less) to remaster TLOU.
Some devs are just slower than others and Square Enix have proved time and time again that they are one of the slowest.
That's the thing tho, even the remaster of FFX+X2 had a bit of work going into it, this just sounds like a copy paste of the steam game onto the ps4 hardware, given the models that it's moving around being so basic I would think you could take a small % of the ps4's power and software emulate the steam version in less than 7months.... if you weren't SE I guess? :<
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