The alternative to not sitting him is reducing his role way down for others. But you're in kind of the same spot as if you did sit him, without the benefit of elevating someone to take the extra snaps.
If Scott takes up a huge percent of snaps, he's still a guy who theoretically does does well the things that should help Fields. Yea they won't have a bailout 6'3" guy, but I think JF is just as comfortable with his smaller bailout receivers as he is a throw it up target.
So then it comes down to, do you want the other 30ish snaps to go to Claypool and the TEs or extra RB, or ESB, TEs, and RBs. ESB can definitely play on ST as well (although he didn't last year he did in his GB years).
Then you have Velus who... Doesn't really provide much if Scott is ahead of him already on KR and WR. There's some gimmicky stuff he could replace Claypool packages with, but he basically needs to replace a ST role/extra defender since they need Taylor for PR.