You are missing something. Ignore target defense only works against non unique monsters.
Also, besides the monsters that have a visible block animation, some block without visual cues (e.g. baal, he has like 40% block chance iirc and he doesn’t have any animation for that).
Which is just bullshiet. All odds are stacked against melee and not only caster gets to bypass all of those crappy mechanics, they also do more damage, have better mobility (in general) AND a metric ton more aoe.