Yes, it is possible.
Maybe.
No.
It's just a fairytale. Won't happen at all.
Reading List (Super behind but reading them nonetheless):
DC: Currently figuring that out
Marvel: Read above
Image: Killadelphia, Nightmare Blog
Other: The Antagonist, Something is Killing the Children, Avatar: TLAB
Manga: My Hero Academia, MHA: Vigilanties, Soul Eater: the Perfect Edition, Berserk, Hunter X Hunter, Witch Hat Atelier, Kaiju No. 8
Well, there does seem to have been a fairly concerted effort, over the last half-decade, to boost the JSA's profile - from their appearance on the CW shows (Legends of Tomorrow and now Stargirl), to having them in the Black Adam movie, to the JS: WW2 animated film - not to mention their slow-burn return in the comics. So I wouldn't be surprised if they do something with them.
They’ll be another JSA run eventually. People always fall back on old/popular ideas.
The movie won’t influence it as much as we might think unless the JSA is heavily included, which I doubt they will be
The J-man
The JSA only gets love in all the other media outside the comics, so I wouldn't get my hopes high.