I'm sure Spence's career is not over yet; he can still fight, so let's wait for his next move. If I were to be asked, I would like him to move up and forget his losses to Crawford. A new weight class means new challenges for him, and I think he will be more comfortable in a heavier division.
It's not yet too late for him to get a fresh start and not yet his time to start considering for a retirement, it's just a single loss and almost every boxer goes through that trouble. And just like how others describe this scenario, it's not about the loss, it's about how would they figure out the things to keep moving after such loss.
And as for Crawford, it's okay for him to fight Spence in a rematch that will be contested at 154 because either way, he will move up towards that division. It will be a win-win scenario because he doesn't have any belts to lose in that division.
That would probably shut Spence up if he still makes excuses and thinks he is more comfortable at 154. However, if Spence still loses, that would make him look bad to the fans, as it's hard to come back after multiple losses. He is probably like AJ, who lost twice against Usyk, and he isn't as popular as he was before.
Anyways, if Spence would want to ensure a good amount of money to be made, a rematch is always the answer since both of them are very popular now. It's an opportunity to easily market the fight. Both moving up would be good, as even if Spence loses, he can still fight other boxers in the same division until he figures out how to start winning.
However, I'm afraid that he will just be next to Crawford, as for sure, Crawford will dominate.
And witht this news,
Jermell Charlo to be stripped of WBO title after fight with Canelo Alvarez, Tim Tszyu will be elevated, the competition would be easy for Crawford and Spence.