It's a whole different narrative. Adriano was a young player we had, loaned away, then sold 50% of his rights only to buy him back when he was at his best. He was an immediate hit upon his return, as expected. And he was at the top of the world.
We "gave him time" only because it was a psychological issue that we tried to help him overcome. We also gave him time and space by loaning him away, then Mourinho tried to re-integrate him in the team. With partial success, but he was a lost cause. Mentally. And it's not like we bought him from Sao Paulo in 2008 and "gave him time". He didn't cost us shit to give time to.
Now with Lukaku we made a record signing. We have to expect someone who is ready and at the top of the game, otherwise all the people shouting "waste of money" are correct.
This guy is not ready, his characteristics that people want him to improve have never been there so it's not a matter of mental recovery - which is insane to consider for a record signing to begin with - but one of acquiring skills he never mastered.
He's not going to be completely useless, but he's not "record transfer" material. At least not for Inter where this was reserved for Ballon D'Or contenders throughout our history!
The main problem we have with Lukaku is that we have no one to replace him even temporarily. Lautaro is the only other proper striker we have and then it's light weight forwards like Sanchez and Politano. Heck, even Lazaro could fit that role if needed. But we may be forced to look for Ranocchia once again if we want a box striker