Not true.
There have been three dramatically different engine designs from HD in the last 20 years; the Shovelhead, the Evolution and now the Twin Cam (four if you count the water-cooled V-Rod).
Braking systems have likewise gone through several periods of technological refinement. Braking performance of Harley-Davidsons compare favorably to the best Japan and the others have to offer. Two and four piston calipers are now the norm on the new models. HD has avoided (for good reason) chasing the two-finger power brake feel typical of the Japanese rocket. Front brakes that can lock the wheel with a two finger squeeze are invitations to disaster in a panic situation.
The multi-port EFI found on the latest crop of Twin Cam equipped Harleys make starting rituals a dim and distant memory. Hit the start button and ride . . .
My Ultra Classic is lighter, handles better, is more comfortable, has a better stereo, carries more, and gets better mileage than a comparable Gold Wing despite the number of times that behemoth has been reinvented over the years. The controls are more thoughtfully designed and much easier to use (apparently the Japanese haven't heard of gloves). The Ultra is a rolling work of art compared to the plastic ensconced two-wheeled Acura, yet concedes nothing in terms of creature comforts. Though a fully loaded Ultra Classic will set you back approximately $1500 - $2000 more than a similarly equipped Gold Wing, you get that and more back in resale value in the very first year.
Harley Davidson factory and dealer support is unrivaled in the industry, regardless of comparable brand. Warranty support is equal to or better than any other brand available in the U.S.
When your old friend becomes 20+ years old (like my venerable FXRS) you can still get parts and service on anything. Try doing that with your twenty-something Suzuki or Kawasaki (or Triumph or Indian or Beemer).
Don't be fooled by the magazine testers who judge technological innovation for innovation's sake as the Holy Grail of motorcycledom. The streets any highways of America are not parsed off in quarter-mile segments; the rockets are no fun to ride unless you're wringing them out to 7/10ths - 8/10ths of your ability or more. Tooling down the road at the speed limit quickly becomes excruciatingly uncomfortable and mind-numbingly boring on the rockets when your adrenaline pump isn't in overdrive. The scenery isn't enjoyable unless its a blur.
High tech high RPM valve trains become a total pain in the a$$ when the adjustment interval comes due. Got a passenger? Forfeit the rocket, unless you're passenger is a card-carrying sadist. Metric cruisers leave you wanting more after a few thousand miles; something real & enjoyable, not plastic.
E-glides were pretty bulky until they moved the engine oil tank under the transmission. It seemed like they took 100lbs off the bike. Dropped the center of gravity and gave the whole shabang a sport feel. '93, I think..... ??
Define better. If I give the Japanese credit it's for the Wing. It has a lean angle significantly deeper than your Ultra so I'd give it the edge in Handling. The real advantage the Wing has is the engine. It's not only much, much faster than your twin-cam, but it's an engine with a duty cycle of 300,000 expected miles between rebuilds. Your Ultra only has a duty cycle of 100,000 miles. Granted that's amazing for an air-cooled engine, but that's exactly the downfall: The limitations of an air-cooled engine.