Steps to reproduce:
1. Open the “CollectionAttributesBug.zip” project
2. Open the "SampleScene"
3. Open the "ReadOnlyAttribute” script (Assets > Scripts)
4. Confirm that the “PropertyAttribute.applyToCollection” flag is set to true
5. In the Hierarchy window, select the “AttributeExample” GameObject
6. Observe the fields in the Inspector window

Expected results: regular fields are read-only
Actual results: regular fields lose the read-only attribute when applyToCollection is true

Reproducible with: 6000.0.b12
Couldn’t test with: 2021.3.36f1, 2022.3.21f1, 2023.2.13f1 ({{Assets\Scripts\ReadOnlyAttribute.cs(5,31): error CS1729: 'PropertyAttribute' does not contain a constructor that takes 1 argument}})

Reproducible on: Windows 10 (by reporter), Windows 11
Not reproducible on: No other environment tested