Yes, but it's not like players have a choice. This isn't major league and minor league hockey. If the team you are contracted to is relegated, you can't just go play in the SHL. Oliver Ekman-Larsson is an example. He played for Leksands at the time, the team he was contracted to. Now they play in the SHL after earning promotion again last year, but at the time, they were in the 2nd tier.
With Tärnström, playing in Allsvenskan is the highest level he can go for this season. That should be his goal. And if he reaches that goal, that's a success.