To say Filip Forsberg trade is one of the worst trade in NHL history is an overstatement. Here are some underrated NHL lopsided trades. (No Messier/Gretzky/Roy trade)
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1) 1975: Detroit traded MARCEL DIONNE and Bart Crashley to Los Angeles for Terry Harper, cash, 2nd round pick and Dan Maloney

2) 1970: California/Oakland traded 1971 1st round pick turned GUY LAFLEUR, Cash and Francois Lacombe to Montreal for 1970 1st round pick turned nobody and Ernie Hickie

3) 1964: Boston traded Alex Campbell and rights of KEN DRYDEN to Montreal for Guy Allen and Paul Reid

4) 1977: Los Angeles traded 1979 1st round pick turned RAYMOND BOURQUE to Boston for Ron Grahame

5) 1967: Chicago traded PHIL ESPOSITO, Ken Hodge Sr. and Fred Stanfield to Boston for Jack Norris, Pit Martin and Gilles Marotte
(Apparently, Esposito had attitude problem but it's still a lopsided traded)

6) 1975: New York Rangers traded BRAD PARK, JEAN RATELLE, Joe Zanussi to Boston for Phil Esposito and Carol Vadnais

7) 1990: Montreal traded CHRIS CHELIOS to Chicago for Denis Savard.
(on the same date 26 years late, the Subban trade happened lol)

8) 2001: New York Islanders traded 1st round pick turned JASON SPEZZA, Bill Muckalt and ZDENO CHARA to Ottawa for Alexei Yashin
(Karma got them in 2017)

9) 1989: Toronto traded their 1991 1st round pick turned SCOTT NIEDERMAYER to New Jersey for Tom Kurvers

10) 1986: Vancouver traded CAM NEELY and a 1st round pick to Boston for Barry Pederson

11) 1992: Chicago traded DOMINIK HASEK to Buffalo for Stephane Beauregard and 4th round pick

12) 1988: Calgary traded BRETT HULL and Steve Bozek to St.Louis for Rob Ramage and Rick Wamsley

13) All Roberto Luongo trade except the last one

14) 2008: Nashville traded their 2008 1st round pick turned ERIK KARLSSON to Ottawa for Ottawa's own 2008 1st round pick and 3rd round pick

15) 1996: Winnipeg traded TEEMU SELANNE, Marc Chouinard, 4th round pick to Anaheim for Chad Kilger Oleg Tverdovsky and 3rd round pick

16) 1982: Montreal traded ROD LANGWAY, Doug Jarvis, Brian Engblom, Craig Laughlin to Washington for Rick Green and Ryan Walter

17) 1992: Calgary trade DOUG GILMOUR, Jamie Macoun, Ric Nattress, Rick Wamsley to Toronto for Gary Leeman, Craig Berube, Jeff Reese, Michel Petit, Alexander Godynyuk

18) All Adam Oates trades

19) All Larry Murphy trades

20) 1991: Harford traded RON FRANCIS, Grant Jennings and Ulf Samuelsson to Pittsburgh for John Cullen, Jeff Parker and Zarley Zalapski

Trading picks that turn into good players don’t belong on this list.

The bruins traded a 5th for Adam mcquaid when he was a prospect. That’s an awesome trade for Boston. That pick turned into Jamie Benn. Both of those statements are true.

Toronto traded Tuukka Rask for Andrew Raycroft

Yeah, like this trade strait up mcquaid for Benn is amazing for Dallas. Mcqaid for a 5th is great for Boston. Would boston have selected Benn? We will never know. Would Dallas selected Benn anyway? We don’t know.

Any Toronto-Boston trade

Yup. Always said it doesn’t matter what player they pick. They weren’t traded for a player, they were traded for a draft pick

the doug gilmour deal wasn't bad they got the greatest coach in the league right now Craig Berube.

Also Blues traded a guy who never played a full season in his entire career for Pavol Demitra from Ottawa
Blues got Tarasenko's first round pick for David Rundblad to Ottawa
Blues got Binnington's 3rd Round for Erik Brewer to Tampa

Rangers get mcdonagh for gomez?

Why are the draft pick trades considered bad? Who knows who the original team would have selected?

HAHAHA! Especially when the draft pick is a 4th or 5th rounder! Every team could've taken Benn multiple times.

Like how would we know that Ottawa would've taken Tarasenko with that pick? Or that Tampa Bay would have taken Binnington?

Fair point, but that Lafleur trade wasn't just about luck. The Seals were horrible at the time and the Habs managed to convince the Seals to give up their 1st round pick (which turned into the 1st overall pick) in order to have a shot at Guy Lafleur or Marcel Dionne. The Habs basically gambled by predicting the Seals would be dead last in 1971. They even made trades to ensure the Seals remains dead last.

Could make an argument that the trades involving early first round picks, but that would assume we know who the team had targeted in the draft before they moved the pick.

The Flyers trade for Adam Oats stands out for me because he didn't do much and then signed with the Ducks in the summer.

Since he was in the news recently, in 1958 the Leafs trade Marc Reaume for Red Kelly. Norris winner and perennial all star, Kelly, had quit hockey in a contract battle with Jack Adams of the Red Wings, Imlach scooped up Kelly for a fringe NHLer and signed him immediately. Kelly was converted to a centre so the Leafs had a centre who could match up with Jean Beliveau. Four Cups later, NHL coach. and a beloved guy in the hockey, business and civic communities, thank goodness Mr Kelly returned to hockey.