Aah, I remember back in the late 80's and early 90's everyone had a boner for microkernels. IBM even gave it a try, attempting to port OS/2 over to a microkernel so they could run it on Intel and PowerPC platforms. At one point, IBM's strategy was that they were going to build OS/2 around a microkernal and then just run THAT on all their hardware, with multi-user and security features added or removed as needed. Well, very long story, very long, they never could get it to work.
Depends on what you mean by that. They couldn't simply port stuff to the new microkernel, AIX, OS/400 etc. wasn't suitable to move to the new kernel. One of the big problems IIRC was endianess.
When the grand unified theo^H^H^H^HOS didn't work out it all fell apart. This in combination with the failure of PPC as a new personal computer platform, the disinterest of others to use the Workplace OS kernel, the failure of Taligent and a lot of other things made sure the project was canceled.
But OS/2 was ported and ran on the microkernel so that part of the project did succeed.
These days you don't see the same hype around microkernals that you did back then. So we should probably warn the HURD team: If your boner for microkernals lasts more than 25 years, you should probably consult a physician.