You can't exactly make that kind of adjustment on the fly.
You really can and teams do, as long as they have the personnel.
One of the problems is that this team relies on just a few players to carry the bulk of the penalty killing.
Tanev. Gourde, Wennberg, and Geekie do all the heavy lifting. Kuhlman gets his fair share when he is in the lineup, but he is scratched more than playing.
Other than that, Schwartz is the only other forward that is averaging more than 10 seconds of PK time per game, and he is mostly only PKing if one of the other four is in the box.
Anaheim was not running the 1-3-1 that is popular right now but they were spreading the zone with two players back on the points, and their forwards playing way outside on the halfwalls. They used a lot of rotation and nearly all of their passes were 20+ feet forcing Seattle to abandon their PK box if they wanted to aggressively challenge the puck.
Getting two defenders to challenge at the same time and the box is wide open.
The coaching staff has to adjust there. The players are being told to aggressively challenge the puck on the PK, but when the opposition's powerplay finds a way to exploiting that(like last night), simplify the PK, and focus on spacing instead of puck chasing and quadrant covereage