The first hour is a thread you can steer. The count is not a ranking switch.
On a YouTube watch page the comment section is a conversation sitting under a video that already has a URL. People who open it read the pinned line first, then whatever YouTube has sorted to the top, then whether the uploader answered. That is the mechanic this page is written for.
A comment order does not place the video on Suggested. It does not add watch time. It does not press like. What it can do is give the first arrivals something to read that is about this upload — a timestamp, a question, a disagreement — so the thread does not open on silence or on a wall of the same three words.
After delivery, the work that is still yours is the part Instagram pages never have to say: pin the one that asks the question you want repeated, and reply in your own voice. A bought line you ignore is a dead thread with extra steps. A bought line you answer is a thread that looks inhabited.