The user interface is way too bright even for daytime use. There isn't even a tint in the white background making the white light from a monitor very intense. Google and DuckDuckGo have dark mode so there is no reason for Bing to not have it when other major search engines have incorporated it into their design. In fact, they already have it on mobile proving that they are capable of adding it to the desktop version of Bing.
Extensions like night eye and other chromium dark mode extensions don't work well with Bings CSS and cause lots of visuals to not render properly on the screen. I use the edge browser and have loved how dark mode has been incorporated into the browser and for Bing (the highly recommended search engine from Microsoft when using edge) not to have dark mode makes it very inconsistent and a flash bang when navigating between Bing and other websites with dark mode.
All screenshots were taken below on Microsoft edge browser (google and duckduckgo detected my browser was in dark mode making the user interface feel more consistent rather than a dark frame around a bright search engine):
Google dark mode:
DuckDuckGo dark mode:
Bing (no dark mode available):
