Here is a list I have formed:
-Switch to Esim
-Build more apartments
-Use shampoo/conditioner bars
-Put carbon labels on products
-Buy stuff at the store
-Eat plant based
-Prioritize transit over cars
-Switch to Ecosia
-Recycle
-Give homemade gifts
-Compost
-Be organized
-Avoid synthetic cloths
-Switch to green burials
-Buy reputable carbon credits
-Mandate microfibre filters for washing machines
-Install Linux on old computers
-Switch to Electric car -Shut down all oil operations
-Pickup litter
-Ride your bicycle instead of the car
-Adopt kids and companions instead
-Build more green spaces
-Convert animal agriculture land to wild lands
-Support repairability
-Ban private jets
18,000,000 kg / 7,000,000,000 = 0.0025 kg per person on earth. 2.5g per person. Its not a big number at all.
Granted, not everyone has a phone or sim, so the number may be 2-4x higher, but we are talking about such a tiny amount of waste that its a rounding error in the scheme of things.