Interesting. The Wikipedia entry mentions SPD and I think that is where I think LEDs fall down—having a skewed and/or incomplete spectrum. Even though it may make certain target colors look correct.

Sunlight diverges significantly from a black-body spectrum because the atmosphere absorbs so many wavelengths.

I didn't want to mention that CRI is matched against the spectrum of _daylight_ because of the confusion that happens with color temperature when you mention the "daylight" word. You're right though, the CRI reference spectrum is matched against sunlight rather than a true blackbody.

Even high cri lights have a huge blue spike that doesn't match the sun. I don't know what chip OP uses, but you need a full spectrum light if you actually want very sun-like light. This page has some details:

https://optimizeyourbiology.com/best-natural-full-spectrum-l...

No idea if there's any evidence or not of the blue spike actually mattering for human biology.

Kind of what I worry about—the spectrum mismatch. Damn but incandescents sound pretty good for just this one application. I must be (am) getting old.