The score says how it ended. xG says how it should have ended: it is the sum of the chances each shot was worth, not an opinion about the game.
A fair draw: the xG gap is only 0.09.
Genoa: −3.6 for the season (19 in the table). Frosinone: +4.8 (6). The gap between points and xPTS is built from matches like this one.