Interesting experiment!
I tried opening this post on a bunch of instances and here is what I found.
- Piefed instances load the image for the counter and increment it on each page refresh.
- Lemmy instances have different behavior depending on whether they enable the pict-rs image proxy or not
- instaces that don't use the proxy load and increment the counter as expected: ani.social, lemmy.world, db0
- instances that use the proxy don't load the image and refreshes on the page don't increment the counter: lemmy.zip
- mbin instances don't seem to display any post content? Unless I am missing something...idk, I haven't ever really used mbin