If views have stayed near the same ceiling for a long time, I would stop treating consistency as the main experiment and audit the first few seconds of the posts that do get closest to breaking through. Compare the opening frame, the first sentence on screen, the topic, and the percentage watched, rather than only comparing total views.
It may also help to choose one narrow audience problem for a short test period. Make several posts around that problem in different formats, such as a quick example, a mistake to avoid, and a simple checklist. That gives you enough repetitions to see whether the topic is weak or the packaging is weak.
I would keep a small table with reach, average watch time, completion rate, saves, shares, profile visits, and follows for each post. If retention improves but reach does not, the subject or audience fit may be the issue. If people leave immediately, change the opening before changing hashtags or audio.