He was bad for 6mil. The bias is some sort of cost/value bias. Happens all the time once a player is getting overpaid. Suddenly they become completely bad a hockey even though if they were on a better deal, everyone would be losing their minds how great they are. It's wild. At 3mil, Myers is fine. If Myers was signed to 3mil for the last several years, no one would have batted an eye.
People also seem to think there's an infinite pile of defensemen available, that the ones that are would simply come for a ballpark number that works. Maybe Zadorov has priced himself out, who know what Tanev wants to do, etc. There's just a handful of capable dmen available and half the league vying for them.