You could also consider doing something about it through something like a fun neighbourhood challenge promoted through social media or another association (like an HOA).
We have a pretty active and usually friendly neighbourhood FB group. To encourage people to consider alternative, climate-friendly lawns, I've been posting photos of the growth of our "bee turf" (a mixture of certain clovers, grasses, short flowers and other plants that need less water and attract bees and butterflies). I got lots of questions about and some people came over to check it out.
We have fundraising events and certain "challenges" in our group from time to time. If you have a similarly active social media group for your neighbourhood, you could post a challenge about, e.g. reducing water usage, AC usage, unnecessary lights, etc. Set a new theme each month and encourage people set their own goal and report on it. People who participate get entered for a monthly draw (maybe local businesses would support it with a small gift card). Tie it to climate change etc and make 2022 a year for your community to come together, learn about sustainability and make changes.
If you don't have a social media network that this would work for, it might be possible to do it through some other association (like an HOA, or your local school).
And if your neighbour isn't aware of it or doesn't seem interested in participating, you can invite them to join in.