Aleyda Solis discusses the importance of mobile-first SEO at InOrbit17, highlighting that search is becoming predominantly mobile-driven and that ranking signals will increasingly come from mobile web presence. She emphasizes the need for businesses to optimize their mobile sites for better visibility, traffic, and conversion, while outlining strategies such as responsive design and AMP implementation. The presentation also covers tools to analyze mobile performance and the significance of understanding user behavior and search intent on mobile devices.