I think those kinds of detail-oriented "practical strides" come when people are using a language for their real jobs. So then the question that should be asked is, "why aren't people using CL for their jobs?"
I find it a bit opposite - "on the job" code is often the ugliest, 80%-done code I've dealt with, with minimal docs, unless a very rare environment not just allowed but pushed for completion.
Things written for public consumption from the outset are cleaner.
I think you're over-projecting your personal experience
> The Common Lisp ecosystem lacks a certain "go-getter" philosophy, needed to forge through "boring" work, that some other language ecosystems seem to have.
"Boring" work that creates something actually useful almost always happens in the crucible of real, pressing problems. Hobby projects tend to focus on what's fun or interesting. People don't want to take the time to bring something the rest of the way into "useful" territory if they don't actually need to use it for some purpose
A lot of Common Lisp code that ends up opensourced is either 80% solutions for things that were necessary for some project (sometimes commercial), and IMO the rare cases where things really got polished - they got polished later on with intent to publish.
On the job code, whether lisp or not lisp... I'm more used to managers preventing writing anything more complete or documented, except for once in few months forcing everyone to write BS low-quality docs because "documentation" is a line item on the contract.
My pleas to set aside time to document and polish things are usually ignored, my pleas for a technical writer on staff to help us keep docs current and well written have never been listened to so far.
My own anecdote is that I've never worked at a company where code quality was chronically devalued; that's only ever been a temporary state of affairs for a specific push, after which time is made available to pay down some of the debt
We're both speaking from limited sets of experiences, and neither is likely to be representative of the whole industry
Of course there's also a chicken-and-egg element