Akihabara jumped the shark almost ten years ago. Now it's mostly a legend fueled by internet wanna-be otaku who have never been to, and never will go to Japan.
I remember exploring the impossibly narrow vertical electronics stores of Akihabara in the late 80's and early 90's and you never knew what you might find.
I still stop by a couple of times a year, but these days it's just a place to find iPhone accessories and old parts for restoring vintage PC clones.
When the iPhone became the #1 phone in Japan, it was over. Just about the only interesting thing about Aki these days is the maid cafes. Everything else is tourist cosplay junk.
They still have many narrow vertical electronics stores in Akihabara. You really still don't know what you might find. It is a real treat. I have been there three times in the past five years and each time has been roughly the same. There are at least a dozen store fronts for each class of component you can think of and they are nestled in these walkways underneath buildings, in alleys, or on street fronts.
Akiba is still the place to go for all those parts, there are just fewer stores and you have to know where to look. I worked at a startup that constantly needed parts for the hardware component and the engineer would go to Akiba, and only Akiba, atleast a few times a month for components for a device that was connected to a vending machine.
You're not going to get a deal on common consumer electronics like a camera or video games, but even still its pretty rare that there is a place where you can go and see nearly any consumer electronic you could possibly want in person.
Zhongguancun in Beijing used to have a lot of emalls, but they’ve been retreating over time as all this stuff moves online.