There is no default that applies (to change the preview appearance) at the time you enter the development module.
There is a Preference setting you can define that applies when you IMPORT files, which will influence the preview in Library and Develop modules.
https://helpx.adobe.com/lightroom-classic/help/raw-defaults.html

The [Alt] function you mention is possibly the 'old' way to set Camera Defaults prior to the Feb2020 updates that changed to the method in the link.
When you enter the Develop module you have choices of Profiles and Presets. (and the [AUTO] button 🙂 )
eg. I have a Preset for my D750 that automatically applies to all D750 camera files at import. Or I can apply the same Preset in the Develop module.