I have just received my new HoloLens2 and calibrated it. I am now trying to get the latest MRTK to use with Unity and get started with development. I understand the current recommendation by Microsoft and Unity for Hololens development is to use MRTK 3.0 with OpenXR.
When I download the Mixed Reality Feature Tool and double-click on MixedRealityFeatureTool.exe file to launch it, I get To run this application, you must install .NET but I already have .NET 6.0.300 installed. I understand from this link that I need .NET 5.0 runtime but when I go to the download page, it explicitly says This release has reached end of life, meaning it is no longer supported. We recommend moving to a supported release, such as 6.0 Runtime.