Netflix is better because they'll stream you 4K video if your TV (and connection) will support it. That's roughly 4x the resolution of 1080p, which I think is as high as standard Blu-Ray will go.
OK, so Netflix has "4k" streams just like VHS-sourced garbage on Youtube is "720p". The source of the video, and the encoding itself, is much more important than the final resolution.
That 12 megapixel smartphone with the tiny lens isn't going to be taking front-page photos for the Boston Globe for the same reason.
Blu-ray is still the best quality consumer format out there, period. Netflix is focused on the smallest files, and the "HD" streams turn into a chunky mess during high-motion scenes.
I hate defending Blu-ray for numerous reasons (DRM, 'standard' that actually wasn't for the first few years, slow menus, etc) but the video and audio quality really is the best we have.