Is their work quality high? Can you dig into how they work faster and leverage them to speed up others? Can you put them on a tiger team, or split their respo

Is their work quality high? Can you dig into how they work faster and leverage them to speed up others? Can you put them on a tiger team, or split their responsibilities so they can move at their fast pace w/o disturbing the team? What exactly is the problem, do the high performers feel entitled to more compensation? Being a senior developer is not about velocity, it's about making other people better. If they aren't doing this - if they are only doing their own work - they aren't senior.