I'd prefer him back for 2026, but agree it's not a given.
The good news is, even with his salary and $28M cap number, they can absolutely afford him. And with older players, I am typically in favor of overpaying for one year vs. being on the hook for longer deals. Do they try and negotiate his $18M salary down somewhat? Maybe. But they don't have to.
His 14 TDs, big play ability, and redzone scoring (contributing to the Rams being 7th in redzone scoring this year) cannot be denied. But neither can the 52.6% catch rate (closer to 51% including the playoffs). That has to be better and could help make the case for a return at a somewhat lower salary.
I would rather have him, allowing for easing in a high draft pick in their top 3 WR, rather than ask a rookie to be WR2 from day one. Plus it pushes Whittington down to WR4 which is more what he is.
I do think part of this is based on what they think internally of Mumpfield as well. Do they think he could be part of the top 3 WR, along with Nacua and a 1st/2nd round pick TBD? Hard to say.