I get what you’re saying, but I think memes like this are trying to do a few things:

• frame mankind’s unique ability to think beyond just the interest of self to drive a sense of common purpose (i.e., increase our chance of survival and avoid self destruction).
• to that end, evoking the construct of a helpless and fragile planet as the calling to fight for self preservation as a species probably works better since all signs point to our inability to act on behalf of a greater good for mankind.
• the imagery and framing of this sort provides subliminal messaging that we collectively and individually have a power to do something about it (humans can create the problem as well as the solution). Honestly, even if it weren’t true, it feels better to think we can affect change rather than not.