Yeah, it's an old argument from people who don't understand how it works - when you open any web page you're not actually looking at it on the internet, it downloads to a temp file on your computer and that's what actually displays on your monitor. Got high speed cable and lots of RAM it happens in the blink of an eye, got a slower connection and less RAM any page with more than 1 or 2 megabytes on it will take a long time to load because it's downloading. Yet people still persist in thinking the restriction should be on image size in pixels rather than file size in kilobytes. Couple comparison examples I made from my oldest daughter's latest Christmas pic;
That one would make most happy because it's 800x600, this one;
They would complain about because it's 1024x768. But if the objective is to save bandwidth the larger picture does a better job because it's a compressed JPG with a file size of 76 kilobytes, the 800x600 is an uncompressed PNG with a file size of 750 kilobytes - the "smaller" image is actually 10 times larger where it counts for bandwidth and loading times. There is some tradeoff in quality for JPG compression, but even 10% compression helps a lot with little loss in quality.

That one would make most happy because it's 800x600, this one;

They would complain about because it's 1024x768. But if the objective is to save bandwidth the larger picture does a better job because it's a compressed JPG with a file size of 76 kilobytes, the 800x600 is an uncompressed PNG with a file size of 750 kilobytes - the "smaller" image is actually 10 times larger where it counts for bandwidth and loading times. There is some tradeoff in quality for JPG compression, but even 10% compression helps a lot with little loss in quality.