“Recent research has shown that red nets are more effective than black or white nets in preventing onion thrip damage to crops, reducing the reliance on harmful chemical pesticides by up to 50%. This approach supports sustainable farming by minimizing environmental impact.”
From this post: https://scitechdaily.com/the-science-behind-red-nets-a-new-dawn-in-eco-friendly-farming/
Changing color of existing nets is a trivial change for such a big gain! Sounds like we can be investigating color as insect repellent for other crops too.