In the fast-evolving landscape of the internet, search engines continuously adapt to user preferences and technological advancements. User experience is significantly prioritized, and one of the major factors contributing to a positive user experience is website responsiveness. A responsive site adjusts smoothly to different screen sizes and device types, enhancing accessibility and usability across desktop and mobile devices.

While modern search algorithms heavily favor responsive web designs, it’s pertinent to note how different crawlers may handle non-responsive sites:
Googlebot: Googlebot prioritizes mobile-friendly and responsive website designs. With the implementation of mobile-first indexing, Google predominantly uses the mobile version of a site’s content for indexing and ranking. Non-responsive sites might suffer in rankings as they don’t align with Google’s focus on providing optimal mobile user experiences.
Bingbot: Bing also emphasizes responsive and mobile-friendly web pages. Although Bing still indexes and ranks non-responsive sites, they place a high value on user experience metrics, which responsive designs typically meet more efficiently.
Yandex and Baidu: These crawlers, like Yandex (Russia) and Baidu (China), are also catching up with the mobile optimization trend as mobile internet usage grows in their regions. Though they may tolerate non-responsive designs to an extent, as global trends shift, they are likely to follow the lead of Google and Bing to favor mobile-friendly sites.
DuckDuckGo and others: While not as explicit about preferences, alternative search engines like DuckDuckGo tend to follow broad trends in web standards. They implicitly benefit from responsive designs due to overlap with larger engines like Bing from which they derive some results.

In conclusion, while some search engine crawlers might still index and provide results for non-responsive sites, the overarching industry trend is clear: non-responsive designs are becoming increasingly obsolete in the face of mobile-dominant web traffic. To maintain or improve search rankings and ensure a positive user experience, migrating to a responsive design is highly recommended.