To add to this: the downstream customers also hate change, just as much as people hate Windows updates. They much prefer being able to buy the same chip for 10 years.

(here at Medium-Size-Fabless-Semi-Inc, I'm in the middle of revving a bunch of parts that are about 10 years old, not because we want to add new features to them but because the process node is so obsolete it's becoming difficult to fab. Yes, they're getting new features, but that's not the primary driver of business)

On the other hand, because parts are physical objects, you can charge money for them. Piracy is .. not nonexistant (ask FTDI) but not a major concern.

There are some interesting corners for rapid-rev electronics, but there's a decision tree:

    - can I do this with a microcontroller?
    - if not, how about an FPGA?
    - ok, there really is no alternative to ASIC, is the market size enough to support that?

Why couldn't a company committed to mask fabrication and wafer fabrication, in concept, perform these steps daily, or several times daily? Multiple prototype designs could be grouped together so multiple customers can realize a new design instance in the same iteration.

With an appropriate debug core in the same wafer, designers who'd completed a tape-out could connect to their chip well enough to repeat their design-verification tests on this real hardware, remotely even (no need to physically handle the device 'til you're certain it's working.) Once satisfied, customers could promote their design to be bonded out for installation into their PCB.

"Sure thing boss, we'll add an extra USART core to this afternoon's tape out."

Regarding hardware, it's not entirely true that it doesn't need maintenance/development. See "stepping" https://en.wikipedia.org/wiki/Stepping_level. There are sometimes ways to tweak the masks to fix a "silicon bug".