Even if they don't get Simmons there is a clear path to respectability next season and that is without breaking the bank in free agency. Even just bringing over Saric and adding two high picks (their own and the Lakers) would immensely improve the talent, but if Embiid comes back all of a sudden there is a real chance of mediocrity next year.
A clear path? I don't see it. There are way too many dominoes that have to fall the right way for this to happen.
1 - Depends on Saric coming to the NBA that year, and actually being effective in the NBA (not a given, since he's yet to play an NBA minute)
2 - Depends on Embiid recovering from his injury issues, having a healthy year, and actually being effective in the NBA (also not a given, since he's yet to play an NBA minute)
3 - Depends on them getting the Lakers pick. If it's protected and the Lakers fall top 3 (which has a pretty high chance of happening) then the Sixers don't get the pick
4 - Depends on them drafting a guy, with either their pick or the Lakers pick, who is able to contribute at a high level in the NBA from the get go (also not a given, as not all good players excel in their rookie years)
If all of the above falls into place then sure, they could turn it around quick. But that's a lot of "IFs", and from where I'm standing it seems the odds are against them.
On the other hand, there is at least as strong a possibility that:
1) They don't get the Lakers pick
2) Embiid doesn't come back healthy or his production isn't what it was hailed to be
3) Saric comes back and struggles in the NBA, becomes a decent but nothing special player
4) Team doesn't reach 0.500 and Noel walks
If all that happens, then this entire Philly exercise is going to look extremely embarrassing, and their head office will be left with a great deal of egg on face.
On the plus side, the latter scenario would prove highly valuable in helping to shush all of those obsessive tank enthusiasts...since there have been few (if any) teams in history who have tanked as hard as this Sixers team.