Funnily enough, the treatment of Croc gives me hope for Smoker.
Smoker’s in the same position now as Croc was at the start of ID. Both really needed a massive powerboost otherwise they’d be irrelevant. Croc at the start of ID was the guy who‘d been beaten by pre-Gears Luffy (and with no Haki, which we were starting to get explanations about at the time). So Oda gave him a big boost and great portrayal, and now when he comes back into the series he could honestly be YC in strength and I don’t think people will bother much.
For Smoker, PH was his Alabasta. All of pre-skip Smoker was an unstobbable beast, going into the timeskip he was still wrecking Luffy in Marineford, and only Hancock could hold him off.
(And Hancock had great portrayal back then, being one of the few CoC users and being unscathed in all of Marineford).
Then for PH Oda decided to use Smoker as the whipping boy to show how hard the New World will be. So hopefully now that’s done he’ll get a Croc-style boost.
Luffy did promise they’ll fight again when they are both at full strength, and it’s been so long now that if Oda actually goes through with it Smoker basically jumps over half the characters in the series in tier lists cause of how strong Luffy is now lol.
It's kinda going in the opposite direction with Smoker though.
If Smoker's Alabasta was Punk Hazard that's a major yikes since it came well after his introduction, whereas Croc was introduced and looked like a monster in alabasta, still gave Luffy the most trouble aside from Kaidou arguably.
Smoker continued to rack up some solid portrayal pre skip, even Ace didn't make quick work of him, it was a stalemate, he got great portrayal like you said in marineford where Hancock had to step in and she has hype of her own.
We went from that to him getting trashed in a later arc. It's like the reverse of Crocodile is happening here lmao, and Crocodile was never disrespected to begin with he just showed up too early but in his given panel time he was never sold short according to the power scale of the time whether it be Alabasta or MF.
I genuinely think Oda respects Crocodile more than Smoker due to this. However despite all of this its true he has more room for growth since he, just like Luffy and Teach, is always actively growing stronger/ranking up (this was also noted back in MF). I have hopes he'll show up much stronger around the commander ballpark, but a lot of the damage has been done as far as hopes go, I don't see him approaching any of the prominent WG members let alone Luffy who is already taking on the top 1 character in the verse.