This post contains a small experiment: a counter which should increase every time this post is opened. Or maybe not, depending on caching. It uses count.ayaya.beauty; hosted by nadeko, a provider of privacy focused services.
Sauce: Zenless Zone Zero
Characters: Jane Doe
I agree that most voters just vote from their feed without opening the post (this is also how I view content here). That is why I am surprised that the counter is much higher that the votes, as I expected the opposite (+ counts from instance auto caches). Then again, there might also a number of crawlers which consume posts on the Fediverse.
Regarding fedia: I too suspect the same issue as with Piefed. I wrote a post in the support community of fedia.io and mentioned one of the Mbin devs.
Also it seems that I hopefully don't have to edit the post after its creation in the future anymore, as there is a PR for Mbin which will enable image-uploads + body via the API (currently the API is quite odd that a thread can be created with either a image or a body, but not both with the same request).