main.parameters.json is required by azd. Landing Zone Accelerator uses main.parameters.jsonc (e.g., https://github.com/puicchan/aca-landing-zone-accelerator/tree/main/scenarios/aca-internal/bicep).

Did an experiment. Using any azd template, I renamed main.parameters.json to main.parameters.jsonc and ran azd provision, I ran into error: ERROR: planning deployment: planning infrastructure provisioning: creating parameters file: reading parameter file template: open D:\codes\devify\csu\app-templates-dotnet-azuresql-appservice\infra\main.parameters.json: The system cannot find the file specified.