While I can see the simple progression from 'a sound' to a sound with an accent (volume/pitch) on 1st beat, and it would be easy to implement, as you said and Damir added, without knowing Bars and Beats, let alone a time signature (and let's park variable tempo, variable time sig songs), it has lower value.
I can appreciate that if you are doing lyric only songs in 4/4 (which is a reasonably common in mainstream western music), then metronome with an accent on beat 1 would work fine.
Going beyond that (e.g. ChordPro markup, multi-time sig support, etc.) may start to take it down the higher complexity/more limited value path, but that is a Peter evaluation to make.