SharePoint Online Date Column Formatting using JSON

Hi everyone,
I've just started experimenting with JSON to format columns in SharePoint Online. I have created an inventory list to track IT hardware. I'd like to have the "Purchase Date" column apply an sp-field-severity--warning class based on 2 years from purchase date. I'm hoping someone can provide some assistance. I've included a screenshot of the list I am using. Any assistance would be greatly appreciated.