I can't see him wanting to stay in San Jose under any circumstances.
Hertl made that GRAVE mistake last year.
Karlsson also made that mistake in 2019 IMO. I think the Sharks acquiring him via trade was fine, but after not being able to get the cup that year, they should have let him walk. That team blew their final load in 2018-2019.
But it also cost them Josh Norris and the pick that turned out to be Tim Stutzle.
And now Karlsson gets to be on a perennial loser/tanker the rest of his career. That team has at least as much work to do as we did when Lou was out. That would put Karlsson around 40 years old by the time they're good again and late 30's for Hertl.