There's a cruel irony in how engineering management attention gets allocated. The people who need it least tend to get the most of it. The people who need it most often get almost none.
Four direct reports is comfortable. You know what everyone's working on. You remember what came up in last week's 1:1 without checking your notes. You can sense when someone's off just from the vibe in standup. Management at this scale is intuitive — you can hold the whole team in your head.