How to reproduce:
1. Create a new 2D Unity project
2. In the Hierarchy, right-click -> Light -> Spot Light 2D
3. In the Inspector, under the "Light 2D" Component, change the "Light Type" to Global
4. Observe the Console 

Expected results: The error about more than one Global Light is thrown
Actual results: No errors are thrown

Reproducible with: 6000.0.66f1, 6000.3.4f1, 6000.4.0b5, 6000.5.0a5

Reproducible on: macOS Tahoe 26 (M1)
Not reproducible on: No other environment tested

Note: The error is thrown when creating the second Global Light in the Hierarchy, but converting the Light doesn't throw an error