I find it kind of hard to explain, I guess the proposal is to add to:
Only bump topics with zero replies
However, this then just opens up the door to the “sometimes I want X and sometimes I want Y” problem. (eg: no reply bump 3 a day, any reply - as soon as one year old and unclosed - bump 2 a day)
I feel this is a good fit for the automation plugin, we can allow for complex rules in that case which can catch edge cases like this, plus we would allow stacking.