Is it forbidden to work for a government entity as an IT systems consultant if there is a possibility of overseeing an electronic system for organizing events that may include musical concerts, taking into account that the work also includes other beneficial IT systems, and that there are significant financial and psychological benefits from this job?

There is no objection to the aforementioned work in general, as it is permissible. However, if it directly involves something unlawful or direct assistance in it, then it is obligatory to refrain from that. For example, supervising dissolute parties that involve impermissible unveiling and mixing or alcohol. A Muslim should not directly arrange for them, advertise them, or assist in them, in accordance with the Almighty's saying: "And cooperate in righteousness and piety, but do not cooperate in sin and aggression."