Hertl and Couture aren't going anywhere. I'll be shocked if Karlsson is traded in the next Calendar year. With those three on the team (or even those two), they'll still be better than Anaheim, Arizona, Philly, Chicago, etc. etc. So, no, that isn't rebuilding, which is why I find it funny some guys (cough Mr. 72) think trading Meier puts the Sharks into a rebuild.
If Grier had already traded Couture and Hertl was moved last year, then I'd be all for getting whatever you can for Timo. Neither of those things has happened obviously. The Sharks have a better chance at becoming good with Meier than they do becoming real bad without him.