How to reproduce:

1. Create a new project
2. Create a new script extending ScriptableObject
3. Create an asset of that type
4. Create a folder with dots (".") in its name, e.g. "a.b.c"
5. Create another ScriptableObject asset in this folder
6. Right click -> Reimport All

or

1. Open attached project
2. Right click -> Reimport All

Expected behavior: Assets are reimported and no errors in the Console
Actual behavior: Asset outside the folder is normal but Asset inside it is not reimported. Note the error in the Console: "Do not use ReadObjectThreaded on scene objects!"

Reproducible: 5.3.7p3, 5.4.4p2, 5.5.1p1, 5.6.0b6