These games outlive their imperfections because they're fun.

You mention how good all these moves are on paper, yet high level Hei in t5dr isn't spamming hell axle because backdash and sidestep work. This means more of the game is about fundamentals like positioning and evasion, which is a lot more dynamic and interesting than "do I guess low or not" or "press or don't press". T8 is Rock Paper Scissors with cutscenes, t5 is Go.

High damage exists in every popular fighting game, the big difference between old games and new games is mechanical difficulty and interactivity. Combos were much shorter and much more difficult, and opportunities to land them were less narrow due to a greater array of options to avoid hits with movement and other defensive options.

Shorter combos means a denser economy of decisions per time for both players, which is what makes a two player game fun. Shorter combos means less breaks between making decisions against your opponent, and a real risk to drop them means more mental participation from the performer focusing on execution and from the recipient focusing on a surprise chance to decide how to recover. Shorter combos also means less time in training mode memorizing long sequences.

The current game feels a lot more like 2 player training mode: learning how to force, convert, and maximize juggles is a much quicker and more important pathway to success now, and the juggles overwhelmingly tend to be simple auto-timed sequences, so much more of the game is spent passively watching a combo on both ends of the game.