It's insane that the Oilers ever drafted Broberg, Holloway, Lavoie and Bourgault in the first place. Those draft picks should have been spent on improving the NHL roster in order to win a Cup while you have the two best players in the league making a combined 20M.
That makes very little sense.
First of, good teams still need to keep a somewhat decent cupboard of talents so they can fill up the roster with cheap talent.
Secondly, the Oilers were anything but a contender at the time they drafted someone like Broberg, otherwise they wouldn't have drafted in the spot they did.
But most importantly: if you want to trade draft picks for good players, you need cap-space to field said players. Three things prevented the Oilers from having said capspace:
1) the cap staying mostly flat throughout this time
2) cap-space being tied to bad contracts they carried over
3) adding additional contracts which didn't work out
If you have no cap-space, it would be completely redundant to trade picks or high-end prospects for players, because you cannot afford to keep these players. It wouldn't have helped to use these picks to make more room either, because then they wouldn't have had any assets to get the players they just made room for.
It's not like Edmonton didn't trade plenty of picks in the recent past when they had a bit of room to work with. In 2023 they only had picks in rounds 2, 6 and 7, in 2022 picks in rounds 1, 5, 6 and 7, and they traded the prospect they drafted in the first to gain Ekholm during the following season. They had no 2nd round pick in 2021, and no 2nd or 3rd in 2020.