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It seems that Input system 1.5.0 is used by default in Unity 2021.3.22f1, which causes crashes, this is a known issue, please refer to Known issues in Unity versions and packages - Mixed Reality | Microsoft Learn. You can find this package in Unity Package Manager->Unity Registry and update it manually.
Also, regarding the packages in MRTK, you can refer to MRTK packages - MRTK 2 | Microsoft Learn to understand their usage, and then choose according to your needs. By default, only Mixed Reality OpenXR Plugin, Mixed Reality Toolkit Foundation and Mixed Reality Toolkit Standard Assets are required.
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