...Now, to directly answer your question towards Capcom and SNK 2D fighters and their arcade perfect variable qualities, you have to look the bigger picture than simply looking the particular titles you have chosen. But for now let's use your examples of 3S and Zero 3.
In reality. 3S and Zero3 ARE quite possibly Arcade Perfect on Dreamcast. And here's why they are... and yet why they are not in the grand scheme of things. 3S on Dreamcast is a result of rebalanced revsion 3 release for the CPSIII hardware. People tend to overlook this fact. This revsion is almost nonexistent in the arcade sector simply due to lack of support from the player base. As such comparisons are (unfairly) drawn between the comomly played previous revision CPSIII release of 3S and Dreamcast version.
The similar also applies to Zero 3 on DC. Zero 3 on consoles laid the ground work for what would become Zero 3 Upper on NAOMI. This includes all gameplay changes more importantly, even perhaps the resolution change that only applies to the Dreamcast (PS2) of the game. People stupidly compare Zero 3 on consoles to its CPSII original release.
There lies another issues with other Capcom non NAOMI fighting ports. Games like SF2X, Jojo's SF III W/DBL Impact lack true arcade accuracy, not due to hardware issue or budget costs, but that of Capcom's counscious decsion making. Things like bugs, infinites and game balance are removed or changed in an effort to create a more polished product than what was possible in the arcade front. The backlash lies in many of the player base ultimately adopting these issues into high level play and actually finding the importance in their implementation and use. The bugs, infinites and other gameplay wrinkles become part of the game itself. Arcade Perfect in a fighter ultimately means Arcade perfect with imperfections. Warts and all.
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