I do not buy this. Having run a campaign through the epic levels, with Expertise, the PCs hit most enemies the vast majority of the time. Sometimes on low single digits. Often with rerolls available for if they did miss. Against the most powerful enemies, ones overlevelled and with enhanced ACs, the PCs were probably looking at a 50/50 hit chance - before adding in modifiers for various powers, items and tactics.
I mentioned another option right above the one you quoted which included a well designed party of optimized characters which will have no problem getting the necessary bonuses to succeed in the epic tier and which will consequently see no difference in the length of combats. Since your group all had expertise, I think that is where your group falls. The example of mine that you quoted is for the PCs that decided they'd rather have Linguistics than an Expertise feat.
An unoptimized character that begins with a 16 attack stat, uses a +2 weapon, and doesn't take a stat boosting epic destiny is looking at a +30 to hit vs. AC at lvl 30. A 30th lvl skirmisher has an AC of 44. That PC has a 35% chance to hit them. Orcus has an AC of 48, that PC has a 15% chance to hit him. CA can increase those chances by 10%. Better stat or proficiency choices can also increase this by 10%. Put this PC in a party which isn't designed to provide them a buff on every attack, and they will miss more than they will hit. An unoptimized PC will also have a poor FRW defense of 35 at lvl 30, which is pretty much an autohit. PCs like this can spend an entire encounter locked down with status effects, and need a buff on every attack to hit more than they miss. The example I quoted is for a party of these kinds of PCs, as well as those that may be missing a role (especially leader or controller). Longer combats with more misses are what they are in for in the epic tier. The feelings of hopelessness comes more from the DM exploiting autohit defenses to take a PC out of the majority of the fight and then either gank them or exploit battlefield attrition to focus fire on the back line. Like I said, they'll succeed, it'll will just take longer and they'll have more turns spent missing or tied down by status effects than they did in the heroic tier. I think this has its advantages, and is fine for many groups. I especially like it in that it makes the epic tier actually feel epic. Hitting Orcus should require careful planning and tactics. I was also saying that this may not be the best choice for some groups. My more casual players, for instance, hated it.
The more this sort of party optimizes by taking expertise, defense boosting feats, accurate weapons...., and the more they choose powers based on what works for the team, the closer they get to the other example I showed which will see no real difference. But this does enforce design constraints on a PC, and that is the disadvantage of compensating for the math discrepancy in this manner. There is less room for characters who would rather choose Linguistics than Expertise or want to use a suboptimal build or even weapon because they think they are cool.
I want my PCs to hit at least 60% of the time, and would prefer it be closer to 75%. Psychological I think it is more fun. I would rather challenge them with deadlier (higher damage) monsters or tactical challenges built into encounter design, than rely on dice roll probability to increase difficulty. So I give them free feats to shore up attack and defense math and still allow them to take suboptimal feats. Combat is a short deadly affair of rocket tag for my my group, and that's what we enjoy. But that's us, other people would hate that flavor.
Fortunately D&D is a vast and nuanced game, with plenty of leeway built into how you challenge your PCs, and how you want to play. Hence my belief that groups should pick their poison, and counter the math in whatever manner is the most fun for them.
