Consider, how many times were there a fight in Delta/Sigma/Alphascape, where the strat was named 'braindead strat'? I don't remember a single one. Now contrast to now, we have Braindead Purgation, Braindead Death's Harvest (though it also gets called JP static positions too), Braindead positions for HC2 final mix (no, not like kingdom hearts), Braindead Intemp (which everyone later hated because it killed people's parses), and last expansion E7S was the pinnacle of 'a potentially interesting fight, made completely trash boring by the discovery of a 'braindead strat''. Closest to 'braindead strat' I remember from the SB days was stuff like Unreal (regular, not uptime) HW, Spyro strat for O10S with that accursed Bulwark that refused to pass properly, and arguments about whether it's better to 'die on 1st vs die on 3rd' in Grand Cross Omega. But nothing was referred to as the name, 'braindead strat'
We don't even have to think about hitting the boss during High Concept. We didn't during Grand Cross either, sure, but we did during Forsaken and Hello World. As for:
Part 1: There is a world of difference between week 1 of that fight and week 'anything past 3', when the hotfix launched.
Part 2: That sounds pretty good, since it'd also mean that other content would have that potential for interesting gameplay from the classes, just without any of the expectations by the game that you'd use it. Like in SB, you could do an EX roulette by just spamming Malefic as AST, and not using any cards at all. But you COULD use cards, if you wanted to. If you're in P8S, you have the skill to adapt to a more intricate job design and rotation. You have to, if you're going to actually learn and solve the mechanics.
Part 3: lmao. Also, it is no longer 'incredibly tightly tuned, no room for error'. It WAS, in week 1. Now? Not so much, thanks to the hotfix, and gear. But even in week 3 it was easier by such a margin you could feel it. Also, is this fight not 'incredibly tightly tuned'? Or how about this one? Seems to me that they managed to deal with their 'more intense job design' and clear despite this supposed handicap. In fact, going back to HW's Creator tier, where the job design was (in some people's opinion) even more 'complex', the world first vid has them kill the boss before it even gets to START it's enrage cast, so even more leeway.
People can adapt, surprisingly enough, to a more complex rotation. Like, I'd personally argue that SAM got 'more complexity' going from SB to SHB, due to having to actually line things up cos of Tsubame's addition. Before that, it was 'spend sen on Hagakure, use kenki on Shinten, remember to save some for Kaiten, Midare if you got all 3 sen and Hagakure was still not ready'. Some people might find lining stuff up to make the 60s loop easy. I don't because I haven't practiced it. But if I WERE to practice it, for example, because it was my main and it just got updated with this new gameplay style, it'd eventually settle into the brain and things would be fine again. If anyone says 'people wouldn't be able to handle it because X Y Z reasons' I think it says a lot more about the person trying to make the argument, than the playerbase they're supposedly speaking for.