What is going on with radio buttons and how did you manage to all of a sudden make them completely unusable???
Your own sample is broken!
https://blazor.syncfusion.com/documentation/radio-button/how-to/radiobuttonfor/None of it works. First there's an error:
The type of component 'SfRadioButton' cannot be inferred...
Even adding a TChecked='bool', when you run the sample and click on a button you get
Unhandled exception rendering component: String was not recognized as a valid Boolean.
I have broken code all over the place after upgrading to 18.2.x!!!
Why screw with something as basic as radio buttons that were working perfectly fine?