I think so. Another reason is that over the course of the season, Paulinho has played better than Dembele. Given the recent play be the other choices available after the first 11, I'm sure Dembele will at least come on as a sub. This first sub is a critical role, could be the difference in this game. If Dembele can come on and spark things up off the bench, that is the sign that he deserves more starts for reasons other than his youth, his potential and his price.
Dembele has barely played this season so how can you compare the two? Besides Dembele has given an assist in almost every game he has played.
Valverde also likes to make his subs after 70th min so I'd rather Dembele start and Paulinho to sub him off.