I do agree we doing way to much to ecosystems but mosquitoes are a problem worth trying to fix, in first world countries they barely spread disease but they kill so many people worldwide with disease. We most likely shouldn't eradicate them for that but something tio mitigate that spread would be amazing.
But horseflies are easy to see, trap, and/or swat. Plus, that ratio might be right, 10:1, but I think my actual historical ratio is more like 400:1, and I’d definitely rather one horsefly bite than 400 mosquito bites