Hello
Thank you for posting in Q&A forum.
NO. If you run the DSREGCMD /Leave command it will remove the device from the hybrid join, but it will not directly deregister or delete the device from the Intune portal. The DSREGCMD command is primarily used to perform join and registration operations with Azure AD locally on the device.
To delete a device from the Intune portal, you need to perform the corresponding actions in the Intune management portal. Typically, you can find the device list in the Intune portal, select the device you want to delete, and then perform the deletion operation. Doing so will unregister the device from Intune and remove it from the device list.
I hope the information above is helpful.
Best Regards,
Yanhong Liu
============================================
If the Answer is helpful, please click "Accept Answer" and upvote it.