The disconnect is where people glommed on to that 55% number like the holy grail, losing context and objectivity. As you level, there are also more buffs/de-buffs available, etc. The "55%" is an average (if you will) but too many gamers now claim that's a right on every attack. While they may have been surprised at the number of people who didn't understand the robust tactical aspect of the game (which I think they planned to account for later, because they did), they built a robust system that handled the "math" so long as people filled the roles and understood the tactics.
Also, if "55%" were a magic number, they wouldn't have had varying defenses between the enemy types (soldier, lurker, brute, controller, artillery).
When they expanded the game, they took measures for people who a) wanted to play non-stat-aligned race/class/weapon/etc. combos, b) weren't grasping the tactical aspects fully and (directly or indirectly) c) optimization players.
When the game expanded again, they took measures for people who didn't grasp, like , understand or want character building/playing complexity at it's current level so they came out with the Red Box and Essentials.
It's been shown time and again the game works fine without expertise feats. They're nifty, but not necessary. "Feat Tax" is an utterly ignorant term with no bearing on reality.
You're objectively wrong. The hit percent was calculated based on how many rounds, on average, encounters should take (during playtesting they occasionally had encounters last 14+ rounds). Based on E/E+1/E+2/etc.
Without Expertise the correct number of rounds are flat out not achievable in Paragon/Epic, even by otherwise optimized characters (exceptions of course exist... if you design the party around this limitation, but that isn't 'fun'). And this issue gets
worse, not better, as you level; despite Expertise, because of the way monster HP/defenses scales and PC damage doesn't.
One of the very strongest complaints I've heard about 4e is combat length. This is a problem I have literally
never had because I understand the math and make sure my group does to. Result: No exceptionally long and grindy combats.
The disconnect is where people don't understand the reasoning for the minimum hit vs even level. It isn't arbitrary, it was a number arrived at for a large variety of objective, mathematical, reasons and was intended to create a parity of experience all the way up to Epic. An E+1 should always take a 5 person party 4 rounds on average. Damage/Hit %/etc need to all exist in relative balance to each other for that to be true. Expertise fixes an error where they
don't exist in relative balance to each other. And, in case you missed it, this is an average, not an absolute. Varying defense levels are fine if you're only trying to achieve an average
You can actually see this with Essential classes. eStrikers are basically optimized out of the box to achieve minimum striker baselines and look how many threads we have with people freaking out that they are "overpowered" or "do to much damage." But I'll cheerfully bet you that an eStriker introduced into a campaign where someone immediately thought that about them suddenly had shorter fights. Their is a straightforward reason for this. eClasses have a much narrower performance band. It is
very difficult to make an eClass perform below the expected mathematical minimum (at least in Heroic, they have the same issues of scaling). Not so for older classes, who often perform
far below with a poor build, especially if they don't take the fix feats.
Ignorance, by definition, is a lack of knowledge. Developers, people who have done the math in the community (extensively) say "This is how it is." You have a
belief about the math (based, near as I can tell, on intuition, anecdotal experience, and the idea that monsters don't get more HP then PCs do damage as you level), but it is no way justified by the numbers. And an unjustified belief is the worst kind of ignorance. You think you know something, but you don't. Socrates said it was poisonous.
