Thank you! We have received the required details. We will work towards a resolution. In the meantime, you may also receive assistance or suggestions from the community members.

If Dell support has not resolve your issue by now, there is a couple of things you can do to check your system.  

First, boot into BIOS and check activity light status.  If no blinking, it ruled out hardware wiring and narrowed down the issue to OS controlled. 

Second, you may try disconnecting the ethernet/network connection and checking if activity light stops blinking.  If it does, it could have been performing a synchronization tasks for account settings or running a scheduled upload from network.  If light doesn't stop blinking, it is narrowed down to a localized activity such as system scan.  You can test with disabling Startup apps and/or Services, one of a time, until you find the cause.

Regarding your concern of unnecessary read/writes to your drive, you may try installing Crystal Disk Info and monitoring information of Total Host Reads and Total Host Writes.  Tracking these information and they will tell you if any excessive read/writes was performed on your drive.  

Beside the NVMe drive, check if you have any other storage in the system.  As the blinking activity light would often coming from a SATA source

Thank you for the sharing the update.