I voted Accidental. The Fighter does not have anime fightan abilities because the designers cannot imagine the Fighter doing it. Its because they don't believe you can do amazing things without magic, or that incredible feats can only be achieved by magic.
I'd agree that it is less that they cannot imagine anime fighting powers, it's that the older school crowd use focus on toughness. There is a percentage of fans who see all warriors over level 5 as "Mighty Glaciers" and see that as super enough to balance against magic full stop and end analysis there.
I mean as much as people say "HP aren't Meat Points" that's how many gamers see it. Crawford and Kendrick was still talking about warriors with multiple arrows sticking in their body in the 1DND video. Whereas to me, unless the arrow is poisoned or kneecaps, the imagery can be of the warrior parrying out of the air or matrix-dodging it.
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But the true issue is that fans want their casters to have magic versatility, power, control,AND stamina and dislike the rules restrictions needed for that to work. Few games and media give spellcasters Versatility, Power, Control, and Stamina
for a reason
In most media, caster gas after a few spells, know few spells, have control issues, fear backlash, are easily disarmed, or have to work hard to power spells.