What exactly is the issue here? I genuinely don't get it. He probably saw that thread from a few years back and wanted to build his own. That thread doesn't describe the process beyond saying that it was hooked up to a DB15 to VGA adapter, which isn't exactly too descriptive. Let's assume he's going to make a video on the process, which he likely is. Then, potentially a couple thousand people will watch that video and learn about the mod, which he'll probably credit where he found the idea from anyway, you're just assuming he won't. And either way, it's a modding idea, not a product that someone made. Should everyone doing a video on recapping a mac credit the original person who figured out bad caps was what made their SE/30 die? Or the first to figure out that tunnel vision on LCDs could be fixed by baking them in the oven?
I'd also not call 15 thousand subscribers "famous" really, there are tens of thousands of channels that have reached those numbers at this point. He's well known in this community, but then again so are you, along with many other members here.
I just don't get the negativity here.