Individual actions to mitigate climate change do count and in the last analysis they count because as these individual actions aggregate, the cumulative effect arises to change systems.
Putting cardboard in a yellow recycling box doesn't do as much as voting for representatives who will work on environmental issues does. Also, boycotting businesses and investing in companies that are environmentally conscious makes a big difference.
Simple example - What do you think the election of Bush over Gore made for US environmental policies? How about Trump over Clinton? How about your state governorship?
Here in New York State plastic bags are no longer permissible for most purchases after March 1, 2020. The heck with the recycling bins, get rid of the problem at its source - get rid of the bags.
My village, Brockport, NY, has been working for the last 3 years on creating a solar farm to create all the electricity for our municipality. That's big. No longer have to worry about turning off the light switches.
Individual actions are very necessary, We just need to become more sophisticated about the targets. The fossil fuel companies want us to sort our garbage as long as we keep using fossil fuels. How much of all this recycling stuff is fueled and supported by fossil fuel industries to fool people into thinking they are doing something to offset the carbon footprint while they keep burning coal, and oil?
Think systemically as well as individually. Unitarian Universalism is a faith tradition based on a covenantal model. It is based on faith in collective activity not individual activity alone. UUs understand that there is more power in solidarity with one another than in individuals going it alone.
If you haven’t done so already, connect with others to work toward the mitigation of carbon emissions which contribute to climate warming.