Based on the goals and budget we've set out for the first "startup module" payload last quarter (see blog post), we don't have a strong incentive to reduce it further. At about ~20 KB it is essentially "small enough".

From today's featured article:

• HTML payload: 63 KB transferred,
• CSS payloads (2): 58 KB transferred,
• JS payloads (3), 256 KB transferred.

From the 256 KB in JS payloads, 25KB is the startup module, of which 9% would be about 2KB. We will instead focus our efforts on the second and third payloads ("page modules"), which are significantly larger where improvements have a much bigger impact. See T233676 for example. I am also continuing (small) efforts that reduce the startup size by simply eliminating modules from it entirely (T233675, T219604, etc.).

Declining for now because changing the registry in the manner proposed would significantly complicate maintenance and debuggability of the system. As such, it is unlikely to be worth the cost of implementing. I speculate there will always be other things we can do that have more value to end-users for the same cost. See also RL Principles.

I am generally open to ideas like this and would be open to revisiting this in the future.