Roma will win against Lecce it's almost certain, even if Lecce plays at home it will be a piece of cake for them to beat them, let's remember that Roma is very well placed in the standings and with a coach like Ranieri they can really make the difference in this final part of the championship
A better ranking in the standings does not guarantee a team can always win when facing a team in a lower ranking like Lecce, because a team like Lecce can also make a good performance that can cause the final result to be beyond many people's expectations. Although before the match started almost everyone might have tipped Roma as the winner in the match, but unexpected results are always possible to happen in the match.
You are right about your opinion in this match. Roma is the better team against Lecce and they will certainly win even when compared in papers. But like you said, when a smaller team plays against a bigger one, it’s not a sign that they will win in that match but anything can happen as football is full of surprises and it can happen to any team at anytime even when they don’t see it coming. If I’m to vote for a winner in this match, it will be Roma and not Lecce as the tendency of Roma losing is low compared to the tendency of Lecce losing in this match.