Real talk, I'm obviously a leafs fan, but on paper the Sabres don't seem that bad. They seem like a play off team. Can someone fill me in what happened? Goaltending the issue?

It was mostly Housley's fault with his systems that he implemented and not getting the best he could out of the young guys. Also he put together horrible line combinations that just didn't make sense

Think you have goon spending crazy. Probably over the cap with bonuses, And then there isn't that much cap space created by expiring contracts for signing RFAs the following season.

We are losing the bogosian, sheary, Sobotka, Wilson, hunwick contract which is around 10.5 in cap space.

Well that's five positions you have to fill. So even at somewhat minimum players that 5m. Then if Middelstadt and Reinhart, could be in for big raises if they have breakout seasons. Look how crazy the RFA has become, almost like a UFA market. Nothing worse than being a out of the playoffs and no cap.

That’s what you have developing prospects for

Yes you are a Leafs' fan. While I am obviously a Sabres' fan, I like the Leafs (except when they play each other). To your question. Before the season started, I thought over 80 pts was a sure thing. Skinner, Sheary and Berglund appeared to more than make up for the lose of Kane and O'Reilly. Adding Dahlin IMO would add at least 5 more wins. After the 10 game winning streak, I modified my expectations and thought they would reach 90 pts but no playoffs. He may not have contributed much on ice, but the team went onto free fall shortly after Berglund left the team, I am presuming he was a positive locker room presence. So to answer your question.
GK, up to the end of the 10 game winning streak, this looked really solid. Then Hutton started to play like a life time back up GK and the rest of the league figured out Ullmark's mechanical flaws. Reinhart inadvertently blurted out the GK deficiencies early then had to back off and try to say he meant something different.
Dahlin and Ristolainen can certainly produce pts. McCabe can hit, Scandella has a hard shot, Bogosian played well through injuries, then who is the 6th defenseman? Nelson never embarrassed himself, IMO Pilut hurt himself shortly after being called up. Comparing the two teams defenses last year, Reilly > Dahlin, Gardner > Ristolainen, Zaitsev > Bogosian, Hainsey > McCabe and how many Leaf fans think the Leafs' defense is bad?
Moving to the forwards Marner > Reinhart; Tavares or Matthews > Eichel; Johnsson or Hyman < Skinner; Kapanen > Sheary; Kadri or Marleau > Mittelstadt. So while Buffalo had one decent center a good LW and RW, TML have 4 good centers and many more good wingers.
Did the team quit on Housley, well I have my suspicions but I will not discuss them on a public forum.
In conclusion, the Leafs were 3rd in the division and comparing the talent of Buffalo and Toronto, Buffalo was at least 6 players away from being a playoff team. Montour cut it down to 5. If Thompson, Mittelstadt and Olofsson cannot step up their game, then there will not be a post season next year. I see promise when Sheary and Rodrigues are together, Girgensons and Larsson control the play, but cannot finish. Okposo's contributions could be filled by a player earning about 1/4 of his salary.
DATM (Dumb A** Tim Murray) set the team back and IMO the re-rebuild started last year at the TDL. I expect the team to improve, Dahlin will give additional evidence that he will be one of the best in the NHL. Eichel and Mittelstadt played better at the end of the season, Reinhart may take another step up the production ladder, Pilut, Olofsson, and Asplund may also be in the NHL next year. These are all wishing and hoping.
Was this a play off team last year, not even close. Too many casual fans (you know who they are when you read their comments) only believe what they hear and what they read, because many do not even watch hockey only the replays.
I hope Betterall continues his methodical steps forward and does not try to jump start.
Go Leafs Go, BTW I hope the more intelligent Leaf fans, will recognize how good the Bruins were and that the Leafs took them to 7 games. So the Islanders swept the Pens, the Canes swept the Islanders and Bruins swept the Canes, but the Leafs took the Bruins to 7 games and every one want to eliminate Zaitsev, move Kadri to Siberia, dump Nylander's salary for anything. OMW, I wish my Sabres had as many problems as the Leafs had. LOL

I'm all for developing prospects, IMO you spend too much UFA money too soon. But I think the Sabres are on the right track if they develop and spend wisely in the next few years.
Actually I'm hoping Buffalo makes the playoffs and wins the championship. That's in February, I'm a Bills fan.