I don't think all Liverpool fans are as happy as you say, they are sorry their team failed to win the Champions League at this high point of the season. It doesn't make sense why the fans should be proud when his team only managed to finish second when they had the chance, that's just not true.
There's nothing to be happy about IMO, after Manchester city beat Liverpool to the title in the Premier League, most of their supporters saw the UCL to be what will give them consolation but they lost out on that as well, next season is another time to give both the EPL and UCL another shot and the team has to start preparing for it.
Mohammed Salah has been a player who has performed well with Liverpool this season, Salah is the Top Scorer in the domestic league this season and Mohammed Salah also received the award as the PFA Premier League Fans Player of the Year.
It will not be proper to only give recognition to Salah for his teams good season, Other of his teammates like Sadio Mane were both instrumental to the teams success and his own success.