A club is certainly more pro-humanity than some of the existing misathropic stuff there like internet.org. Philanthropy doesn't have to be about giving money.
Per RFC920[1], which defined the initial TLDs, the ORG domain was for "Organizations". It doesn't say anything about "ethos", not-for-profit status, etc. It's for "organizations".
I'd love to see a citation re: this "not-for-profit" designation being codified somewhere by IANA. It's not supported by RFC 920.
I'd also love to see something indicating it is for big organizations only, which is patently false. Obviously it is irrelevant why it has that ethos as long as it in fact exists (if you want to pretend the general public doesn't see .org as generally indicating a service to humanity rather than a commercial venture, we can just agree to disagree). Also, in the doc you link it is clearly, evidently, for non-commercial organizations since .com comes first and covers all commercial entities, and.org is for all other entities. It is part of the Public Interest Registry. The point is there is a legitimate reason to want to use it, even if you are small - and no good reason to force small NGOs to abandon it other than to increase profit extraction from non-commercial organizations.
I don't have a thing to say re: "big" vs "small" organizations using the ORG domain. Nor does the RFC say anything about it. (Perhaps someone else in the discussion was talking about organization size, but it wasn't me...)
re: public perception vs. definition - I'm not "pretending" anything. The RFC doesn't call out that ORG is for not-for-profits, or for organizations related to any particular "ethos" or philosophy. People can think what they want about it, and organizations can try to use the public perception of ORG to influence public perception of their organization however they want. That doesn't change what the RFC says, which was my only point. The RFC doesn't specify who it is for, beyond "Organizations". This notion that ORG was "reserved" for not-for-profits seems to be completely lacking in evidence.
It is specifically for "other" organizations, ie those that don't fall into the categories above. One of those categories is for-profit, ie commercial, organizations. It's not for all organizations including the above, but those that are not the above. It's pretty clear.
I think it's an implicit read, that is, given that anyone commercial should be using .com, anyone using .org should be non-commercial (and likewise non-educational, non-governmental, non-military).
That being said, it's not like .org has, in practice, ever been exclusively for non-commercial entities or non-profits.