[the_fall]

Because inexplicably, there's random pixel-level noise baked into the blue area. You can't see it unless you crank up contrast, but it makes the bitmap hard to compress losslessly. If you remove it using threshold blur, it doesn't change the appearance at all, but the size is down to 100 kB. Scale it down to a more reasonable size and you're down to 50 kB.

Modern web development never ceases to amaze me.

[SahAssar]

None of this is due to "modern web development". It's just about a dev not checking reasonable asset size before deploying/compiling, that has happened in web, game-dev, desktop apps, server containers, etc. etc.

This should be an SVG (a few kb after proper compression) or if properly made as a PNG it'd probably be in 20-ish kb.

[Mordisquitos]

The dev not having the common sense to check file size and apparently not realising that the PNG format was being grossly misused for this purpose (by not even having a single tone of white for the J and the corners, let alone for the blue background) is modern web development.

[edflsafoiewq]

What is that noise actually? It's clearly not JPEG artifacts. Is it dithering from converting from a higher bitdepth source? There do appear to be very subtle gradients.

[gryffyn]

I would bet it's from AI upscaling. The dark edges around high contrast borders, plus the pronounced and slightly off-colour antialised edges (especially visible on the right side of the J) remind me of upscaling models.

[Mordisquitos]

Not even the white is pure. There are at least #FFFFFD, #FFFFFB and #FEFEFE pixels sprinkled all over the #FFFFFF.

[theshrike79]

I'd bet that it's AI generated, resulting in the funky noise.

[edflsafoiewq]

Oh, ding ding! Opening in a hex editor, there's the string "Added imperceptible SynthID watermark" in an iTXt chunk. SynthID is apparently a watermark Google attaches to its AI-generated content. This is almost certainly the noise.

[car]

Make it an SVG and it's down to 1kb.