I think the larger issue isn't so much that champions like
and
lack utility (Darius technically has some utility in the form of his slow, pull and movement speed boost), but rather that they're built specifically to duel other melee champions, to the detriment of everything else. Often, this translates into tons of free stats and steroids (Olaf being the most egregious example, with his three/four separate stat boosts), and more generally a focus on raw stats and reliable fighting power versus more interesting and unique contributions. Going back to the ranged vs melee argument a while back, a lot of melee champions tend to suffer because they either get up close to their opponent and DPS them to death, or just get kited too hard to make an impact, and depending on how tanky they are will always tend to fall into one situation or the other over every game. It's the reason why ranged versus melee tends to heavily favor one or the other over the course of a patch cycle, and why melee top laners tend to suffer against ranged champions. We need each fighter to be able to do something unique besides duel, and have something to bring to the table besides raw tanky DPS. Even super-kiteable champions like
and
can make an impact against kite-heavy comps, and bring unique power to their team that no other champion can replicate.
Darius technically has the tools to be a really cool and unique bruiser (he works like a time bomb, something Riot wants to bring out in him in his eventual rework), and Olaf might not even need that many fancy changes to become genuinely powerful and worth picking, but both need to have some outplay potential beyond just getting kited. A big problem with a lot of bruisers is that they're super-reliable, so while they don't have that much variance when it comes to using their spells (you can't really "miss" as a bruiser, in most cases), that also means there's a cap to their performance that limits how effective they can be (hence why a lot of bruisers dominate in lane but underperform in teamfights). While reliability can be a form of power, it can become very dull if it doesn't allow for high moments in a champion's kit: right now, there are very few high moments in top lane (pre-level 6, at least), since most fights turn into stat-offs (or slap fights), where the champion with the highest DPS and tankiest stats wins, but either side can just sit back and use their free sustain to heal back. Few abilities are impactful enough to make a lasting mark in top lane, and most bruisers are built to shrug off a large part of the damage they receive. As much as people like to complain about the likes of
or
, whenever they initiate a combo, that combo hurts, and can't be healed back easily. They're capable of making plays even in lane, and create high moments for both themselves and their opponents. On top of that, they bring power nobody else can copy, whereas it's difficult to differentiate between the contribution a
makes versus, say, Olaf or
, despite differences in their kits.