Yes PS4 has its limitations, but it's hard to believe that the same system would hit PS4's limitations first before it hits PS3 limitations. PS3 is clearly the least capable of all the platforms currently officially supported by FF14:ARR. Some people may be playing on 10 year old PCs, but if one is using a PC for gaming, then one should realize that 5 year old PCs are already too old. PCs spec hurdles are raised much faster than consoles.
So when talking about hardware limitations, it doesn't make sense to not talk about the least capable platform, i.e. the PS3. Even PC's have limitations, but when PS3 is sitting there at 1-star level, there's no point talking about a 3-star level limitation.