Yes, SEO plays a big role for Affiliate Marketing, reason is SEO is the only way to get quality advertiser or publisher lead which will help that business brand grow or sell the product online.

If you want to do Affiliate Marketing of your product as the brand owner to grow your business online or if you're a influencer or publisher who want to monetize their audience via Affiliate Marketing programs then SEO is the priority choice or backbone.

You must do website SEO optimization, AEO optimization, LLM optimization for your business growth as a part of your digital marketing strategy for Affiliate Marketing growth.