Some great insights here, thank for writing—my main takeaway is that sharing and informing the team how well adopted the design system is, and the direction to head is a powerfully motivating tool.
On the one hand a suite of products and teams of varying codebase quality can be challenging to assess, but you could use it to pit teams against each other. Imagine awards for "biggest improvement" or a leaderboard of token adoption!
Love the "orphan explorer"—I haven't used it myself, but I've seen Figma's organisation plan gives you metrics where designers have "detached instance" and how often. That can be helpful for assessing (non) adoption on the design side, and where to probe.
Another great article I can recommend for readers: where you might place your efforts, changes depending which stage of "design system maturity" you're at: https://medium.com/design-systems-for-figma/creating-components-for-mature-design-systems-f31ecc85627a