Can someone call @graeme to answer this question?

I found the an (old) answer from Graeme on Quora that explains the difference between Grails and Micronaut - it doesn't answer your question directly, but it perhaps provides some insight into how he sees the two frameworks:

I think Graeme left the Grails team and now focuses on the Micronaut framework, taking away the great ideas of Grails and leaving behind only the code. I miss him so much, but you can get a feel for his ideas along the development iterations of Grails versions 2 to 3.

He left for sure, and it’s okay, life is a continuous change, I am just trying to understand if a Grails version based on Micronaut is possible. Since they introduced it in the core and not as a plugin, I thought it was a starting point of a transition from Spring to Micronaut. I still think that Hrais should take a step back and keep only Spring. Grails by itself just need to stay updated, all the evolution can be on the plugin side.

Maybe possible but the framework should be totally rewritten and called ‘micro’’, I will give it a try and see if it’s the right one ☝️