No, I'm not. The term open source is defined here: https://opensource.org/osd

Copyleft, free software, and open source all have different meanings, and GitHub has no restrictions on the license of software using its platform, and you're deliberately confoudning these things here to sow confusion. There are millions of different software licenses, yes, but that doesn't make them all open source. Give me a break. Is Windows "open source" by your reckoning? I has a license, after all, and I can decompile it, after all.