And you don't need to open the packaging to read the serial number. With a strong light source, you can see the serial number through the anti-static film in which the hard drive is wrapped

This depends on whether you receive an OEM version (for system integrators) or a version for end customers from your dealer. Seagate does not provide a warranty for OEM hard drives, so you can only contact your dealer in the event of a warranty claim via the statutory 24-month dealer warranty, and Seagate only provides a 5-year warranty for models intended for sale to end customers.
You can check which of the two applies to the product you have purchased by entering the serial number here at Seagate: https://www.seagate.com/de...

I don't care about that.
I've never had a Seagate break.
Warranty is more interesting with Western Digital!