To me, there are four categories of monitors: Mastering, mixing, reference and tracking.
Mastering needs to be full range with very flat response and no dips.
Mixing needs to be full range with no midrange dips.
Reference is to check balance compatibility because really flat monitors can sound ok with many barely acceptable balance choices. The thing is you really don’t want to equalize based on what you are hearing on a reference monitor.
Tracking requires the same capability as mixing with the additional ability to survive high playback levels and accidents such as a dropped microphone.