I think they had no illusions before the game started, so there was no disappointment either. On the contrary, they met on the same field with players from a top team and I think for them this is a great memory for life, not everyone will ever be able to go to Europe and play even for a weak team in a top league.
By the way, I heard that the fans' interest is unusually weak - even at the PSG - Atletico game, something like 25% of the seats in the stadium are occupied.