If the OP was "shadow banned" his posts wouldn't show up when I search hashtags he uses in his posts.
This is one of the things I hate about so called social media entrepreneurs,
as soon as their content isn't getting the same level of engagement as it did in the past, it has to be a grand conspiracy. You start to hear them talk about algorithms and shadow bans because it's not a claim they can back up with any evidence.
In fact, laypeople buy into these outrageous posts and echo the sentiment which can artificially inflate the engagement again.