Can motherboards, graphic cards, CPUs, etc., be stored in vacuum sealed plastic bags? If so, would this extend the shelf life to any degree?

that would be an unneeded expense; and you would be laughed at for it.

for the average board, placing it on a shelf would do well. however placing plastic against it and then pulling the plastic away could cause static issues.

you can purchase special anti static bags but they are expensive. i have several and do not use them at all.

vaccuum sealing a board will not make it last any longer.

 

the greatest threat to a board is static discharge.

always remember to ground yourself out before touching electronics (especially in the winter).

you can do this by touching something metal.