I think it depends on his future aspirations. If he still wants to play in the NFL as a QB, he probably needs to go elsewhere. However, if he is ready to embrace the idea of one day being a coach instead, I can't imagine a much better place than at Alabama. Another year to study under the best in the business, who has pretty much the best coaching staff at every position covered.
My first thought, though, was how his staying might affect our two incoming QB's and Mac Jones. I think we would lose two of the three if he made that choice. Unlikely we keep both Tua's brother and Tyson for their entire careers as it is, but add in another person between them and the starting job, and one or more could make other pastures look greener.
Ultimately, I just hope Jalen makes the choice that will allow him to be as successful in his life as he can be.