So it seems to me like when the same was initially in development, it was aimed at current gen consoles, but after the first set of delays, the game became a next gen title, which meant that it would be CPU-limited on the current gen consoles, thus needing more optimization on it while it runs fine on PC and next gen consoles.
As for which condone version to buy, I think you can get the PS4 version which should work on PS5 in compatibility mode, and it'll get a next gen upgrade for free anyway in a few months.
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