Yes but (deja vu here) pumped hydro storage benefits from geography, so it's only a solution for Norway and Sweden and other bumpy places.

This thread was about Denmark, but obviously the solution will be different everywhere. Some places have suitable geography, others have more sun and milder winters where overbuild+batteries are easier, some have existing Nuclear that can be kept running affordably, maybe you even have politically stable neighbors where a HVDC grid can smooth out differences in weather, there are no generic answers.