Earlier quoted context omitted.
Since he doesn't summarize the test above, let me. The jpeg.io result is bigger than the other two and noticeably worse quality. The problems were with the sharp lines. Perhaps jpeg.io specializes in photo-realistic pictures rather than graphics and logos.
jpeg.io may have lost on sharp lines, but it had WAY fewer artifacts than either of the other exports, and the blue was closer to the original compared to the Photoshop export. In my opinion, it's a better quality image.
For me, it looks like a different image. As in, I would never have expected that the differences to the original weren't a (bad) choice by the "designer" making the image. That seems risky, and in many use cases a worse kind of artifact.