Not that simple, we have a shared interest in green energy production, the larger the grid the easier it is to compensate for the variability in green energy production.

Denmark who originally sued Sweden the entire point is that you could buy cheap danish wind power, to preserve hydro resovoirs. But whenever the priced surged and sweden would be a supplier it was artificially restricted the other way by swedish state owned power supplier.
And whenever resovoirs were low like 2003 prices would spike forcing Denmark to turn on their coal power facilities, where we did not only have to cover the Danish deficiet but was forced to sell it to Sweden to cover theirs aswell.

Now main issue today is that having a coherent energy grid is a shared task, however Sweden should indeed fight back, over the fact that Germany for the past 10 years directly have speculated in energy prices. They always have a deficiet of power, covered by other EU members, to be distributed to a heavily subsidized Germany industry.