It's a 🤬-storm of an issue that most people are unaware of until the moment they have to replace those suckers. Finding out your standard clutch job costs two to three times as much as before? Not fun.
That said, standard flywheels are also wear items. But they wear out so slowly that we basically ignore replacing them unless something goes bad.
A Dual Mass Flywheel is a needlessly complex piece of equipment. We already have crank dampers, balancer shafts and counterbalance shafts to quell vibrations. The DMF exists only to quell out that last bit of vibration they can't damp out and to absorb shock loads during shifts. Something that can be done with better engine mounts and ECU programming that smooths out torque delivery.
That's the bit that kinda annoys me too. Modern engines would still be incredibly smooth and refined even without DMFs. Heck, a lot of those switching to 3-cylinders now use weighted crankshafts to smooth vibration. I don't know if those are any more or less reliable (how badly
can you cock up a crankshaft?) but I'd prefer it to a grand's worth of flywheel that, if you're unlucky, needs replacing every 5-10 years.
On a related note, you mention them being used to absorb shock loads during shifts. If that's why so many cars have such a vague feel between clutch and shifter these days then you've just given me another reason to hate DMFs.
Since we're on about how great manuals are, if I'm gonna have a manual I at least want to think a smooth shift is all my own doing (with a little help from the synchro rings, of course, as Danoff would point out...).
Hear hear. People rag on Prii, but that transmission and engine-electric motor combination are incredibly robust and reliable. Sadly, as a planetary has a limited effective speed range, you would still need some way to switch from low range to high range gearing in a non-hybrid with a planetary.
Yeah. But that may not be an issue if more cars become hybrids...
Hell, if a manufacturer sees fit to deliver a manual transmission car with manual idle control, ignition advance mapping control and fuel mapping control at my fingertips, I will be deliriously happy. 
The child in me wants that too, if only to have a big row of switches to flip and levers to pull so I can ricochet down the road like Toad of Toad Hall
Say whatever you like praising automatics, they'll always be inferior in multiple ways.
Price
Weight
Control
Mastering something difficult (instead of asking it be done for you)
It depends exactly what you want from your driving to how much any of those matter, though.
Price - people are prepared to pay the extra to have their car do the work for them sometimes - see virtually any modern car technology.
Weight - Without comparing side-by-side, is this something you'd really notice? In fact, could you hand-on-heart say you'd notice the difference in weight between an auto and a manual without being on a race track? Even then, I suspect it'd be small. There's more difference in the weight of different engine capacities, and on a track the different driving characteristics of auto and manual would probably affect lap times more than weight.
Control - Ultimately, an automatic drivetrain responds to your right foot slightly slower than with the direct drive of a manual (though I say this loosely - I've driven plenty of manuals with awful throttle response - and I think I mentioned it earlier actually, but I find throttle response much more important than the way the gears are being shifted). But control has penalties as well as benefits. Is it "control" every time you cock up a shift? Every time you stall? Every time you crunch a gear? Or is it "control" to pull a paddle and have the gearbox do exactly what you want, exactly when you want it?
The analogy here is whether you use the remote or get off your ass to change the TV station. You're getting a different channel either way and you've been able to control what you see - it's just a different way of going about it.
Mastering something difficult - Again, I can appreciate this. I taught myself rev-matching and now do it as second-nature. A friend pointed out I was even doing it in a diesel, high-roof, long wheelbase Transit van a few years ago
Heel & toe I've not mastered yet - introducing the brakes to rev-matching is an extra area of difficulty, and not an easy one to hone on the road. Ditto left-foot braking. But who is to say that it's an important part of driving? I can't drift either, but that doesn't mean I can't have fun behind the wheel of a rear-drive car - something doesn't have to be difficult to be enjoyable. I find driving itself, whether manual or auto, pretty damn easy actually.
I also have and '06 ZX6R, but all bikes are manual...
