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There isn't much Square can do other than being consistent with their quality and releasing their games on multiple platforms whenever possible. Rebirth's gameplay is great and combat system the best in the series (general consensus) and may well be my favorite in any RPG or action game ever. The controversy is mainly the plot and segmentation.
Timed exclusivity on popular platforms isn't bad for companies and has nothing to do with Rebirth underperforming in the long run. Most potential buyers will either buy it on PS5 or wait to get it on their preferred platforms, leaving an insignificant minority to skip it out of spite or because "it's an old game bruh", a minority so small, they could be cancelled out by double dipping on Switch 2 for portability or PC for higher fidelity/custom experience. Not to mention the money SE gets from Sony and Epic Games.
I also think some people are massively overrstimating how much Rebirth cost to make. Game only took 3 years to develop, and the sequel could take less. That's 3 years from a company that isn't exactly known as efficient.
