You're still doing it ...

It's one thing to treat open source like a giveaway and an other to treat it like infrastructure. If that difference doesn't matter to you then there's probably no reason to continue this conversation, but since you asked:

The main downside of the MIT license compared to the GPL is that it doesn't guarantee that derivative works remain open-source. This exposes code to a few key risks:

• Proprietary "Forks": Companies can take MIT code, make improvements, and sell a closed-source product without contributing anything back. This is its biggest weakness. Competitors can create modified, closed-source versions that might splinter the community and reduce its control over the project's integrity.
• No Patent Protection: MIT offers no explicit patent grant, so if a user of your code is sued for patent infringement, the MIT license offers no defense.

The GPL's "copyleft" policy is specifically designed to prevent these issues by ensuring that modified versions distributed to others must remain open source.

The good news is that code under MIT can be re-licensed as GPL by the copyright holder, but not the other way around. Unfortunately that sort of change probably won't sit too well with uutil's funding agreements.

If I were to depend on this project, 5 years from now, I’d rather not wake up to find the core contributors sold or yielded to a closed-source vendor.

Notice, I didn't once go after anybody with personal attacks over this. You couldn't seem to stop yourself.