The smarmy dishonesty about "expanding the Notepad++ brand" actually is selfish and ill-intentioned. Perhaps he is too young and naive to fully understand that he is being parasitic. But naivety is a well-travelled path towards malice.
Regardless, he absolutely deserves to be shamed on GitHub for this. I don't like the online culture of public shame and sandbagging - I think this GitHub thread should be closed now that it's viral - but sometimes people actually do things they should be ashamed of. This needs to be a tough lesson.