What you guys are mistaking for production numbers (quantity) is actually down to budget and fixed price points of our market. Western retailers prefer fixed price points, which for the toy company determine the cost of design and production.
Specifically for Alternators, Hasbro wanted to sell the toys at $20 USD, so that meant all-plastic pieces and some sacrifices on paint where possible, otherwise the (very complex and expensive-to-produce) toys would be unprofitable at the $20 price point. Remember, they're selling in a market where corporate retailers control things, and it is quite likely that a higher price would be unacceptable to the retailers for a product that small.
Japan's different (smaller) market allows for a more flexible pricing system where toys in a line aren't rigidly priced by how big they are or what is in them, but by how much they think they can charge for it. For example, during Superlink, Takara removed the electronics from nearly all of the Autobots, but kept the prices the same as the Decepticons, who retained their electronics. Wing Saber was priced slightly more expensively despite still being considered (at least internally) as a Mega class toy.
Also, demographics, Hasbro primarily deals with a massive mass market, selling to major conglomerate retailers who primarily sell Transformers to children. By comparison, TakaraTomy is clinging onto a niche of dedicated (though a small number) of Japanese collector fans, so they pretty much *need* to throw some extra money into their decos because their primary customer base expects it in such a demanding market.
This is not about Hasbro not giving a shit about customer satisfaction or Takara caring more because they're Japanese (I would consider that a western stereotype), but different markets and different budgets at play.