Simply market and manufacturing inertia. They cannot, or more accurately will not, make the simplest changes to improve the machines.
I think we do underestimate the cost and 'potential risk' of these small (sometimes teensy) changes when applied at scale in manufacturing.
The tooling is set up as it is, the components are in stock at the factories in large quantities, and the workers are used to the process the way it is.
The costs of what appear to be a trivial change, when scaled over tens or even hundreds of thousands of products, can mount up.
Even if someone persuades the bean counters that the innate costs of a change are proportionate to potential increased profit, there's the risk of rhe change.
"
Sure" says the Financial director (or "Commissar for reducing waste to avoid getting shot", or whatever they're called in China
) "
We'll make this change and assuming the change broadly goes fine, the product will be be better technically and our customers will like that and sales will go up and our turnover will go up and more than the change costs and all will be good. But what if everything doesn't go broadly fine? I'll be sacked" (or shot if they're in China).
And yeah, if we're realistic about the way the world sadly works, they make logical point.
Companies (and I mean the organisational entities, not individuals within the company) are not working
primarily to service customers or even sell products to customers; thats just what is making them money.
They're working to make the positive gap between the money they make and the money they spend, as big as is humanly (and generally not
humanely) possible.
(and, of course, the individuals within those companies are, themselves, working to mostly to maintain their/their family's income)
If Ford or Starret or HP or Google or Amazon or Seig or Weiss or whoever, could make lots of money by putting cute little kittens into industrial liquidisers and comfortably get away with it, you can bet they'd be in the kitten smoothie business.