The team he took over had allowed the most goals against in the league, missed the playoffs, and was on the verge of seeing the franchise face walk away for nothing.
I'd ask you how you consider that "playoff-caliber", but I don't really want to hear the answer.
The team made the playoffs 3 straight seasons and got to the CF in two of those three seasons, getting to the second round in all three. That automatically made Lou the most successful Isles GM since Torrey during the Cup years. As in, matter of factly.
And even though I've often critiqued here that I've never seen a team move 4 straight first rounders without being in the midst of winning Cups, which we're obviously not, the farm has not been sold. The verifiable bluechippers may not be there, but there's plenty of NHL material in the system.
And save for Dobson, Romanov, and Nelson (each with 2 more years on the current contract), the absolute key guys on the Island are signed for a good long period of time. The franchise has no need for anyone in the system to usurp Sorokin in goal, Pelech/Pulock/Mayfield on the blueline, or Barzal/Horvat up front. Meaning, key positions are taken care of moving forward and then either the system or free agency can be used to round things out or even bolster them up accordingly.
The situation is not nearly as dire as you're making it out to be.