On whether stopping matters: yes, and not for the reason people assume.
It is not that an audience drifts away in four weeks - mostly they do not notice. It is that the habit is what is fragile. Four weeks becomes three months becomes never, and the thing you lose is the practice of noticing what is worth saying, which is a skill that decays.
What keeps it going through a quiet month:
Lower the bar deliberately. A short note beats nothing, and a nothing week is where the habit dies. Two sentences and a screenshot is a legitimate update.
Keep a running note of small things as they happen, so you are never starting from a blank page. The thing that annoyed you on Tuesday is a post; you will have forgotten it by Friday.
Separate cadence from news. Post on a schedule regardless. Some weeks it is substantial, some weeks it is a paragraph. Consistency is what builds the thing, and waiting for something worth saying is how people stop.
And honestly: if you need a break, take one deliberately and say so once, rather than fading out. That is a different thing from drifting, and it is much easier to come back from.