This was not a man of austerity.
The only way he's able to convince a long-retired Rocky to be his trainer is, again, because of his dad. Anyone else who mentions Apollo to his face is likely to get punched out, but Adonis doesn't approach Rocky under his pseudonym -- he name-drops his dad within two minutes.
Then he's offered a showcase fight on HBO despite being woefully inexperienced. Why? Because they can promote him as Apollo Creed's son. So does he reject the offer to pad his record and organically build up his own following so he can eventually earn the shot on his own? Nope, he changes his name back and goes with it.
Why waste all that time grinding when you can visit a trainer and jump to Level 80?
Adonis Creed isn't a great underdog; he's a privileged kid who is tone-deaf to the advantages life has given him and thinks he got everything on his own. It could've been called Trump.