This dad exists in a future with not enough oxygen in the air, meaning multiple decades from now
This is, therefore, not about something an actual person has done, but about something people are doing now.
People right now say the state can not invest money into clean energy as our children would bear the dept. This makes it so that future generations will actually have to invest significantly more money to fix problems that could be avoided relatively cheaply
The post is doing the best it can to make it easily understandable that saving money for the sake of saving it is not a solution, hopefully getting more people to share this opponion
I neither see something this post could do better as a metaphor nor the point of your criticism of it