Whenever I'm playing a game via emulation and I get stuck, I do end up wondering if it's a bug in the emulator. This particular issue, I would have assumed the game was designed this way it and is just difficult.
Not quite related, but i get a similar feeling if the game seems really tough: "is this due to emulation latency". I went down a rabbit hole on this one and built myself a mister FPGA!
I only ever played DKC on ZSNES, and I had no idea that this was an emulator bug until reading the article. Like you said, I just assumed that it was the intended game design to time your launch from the barrel so that it was the correct angle. It blew my mind to learn that it was a bug!
I played a lot of bionic commando as a kid. When I loaded it up in an emulator in the early 2000's it was way harder than I rememberd. Then I realized there was an emulation bug where the enemies didn't disappear when you blew up the base, but Ladd still froze; that meant I needed roughly 2 extra life points when clearing a level. Just to see if I could, I did beat it that way once, but never again.
Why did I get downvoted for this?
Chronic Trigger had one like this. I recall there is a section where you catch a rat and have to input four simultaneous key inputs after catching the rat. But usb inputs only forwarded 3 at a time so to get passed this you’d mash all four and eventually you’d get them registered inside the very short timeframe. Took many tries and was very frustrating.