I really think the issue would be load on server bandwidth (depending who’s hosting the image). 2mb is not good for client performance, but in the grand scheme of things it’s not that much data. Video streaming consumes so much more. I would like to see smaller images so clients can load a feed of images faster. It’s also annoying because Lemmy doesn’t always tell you the size of the images. So the height of posts will shift in your feed as images are loaded.

lemmy shouldn’t require posters to compress their own images. Compression should happen automatically. It will save both the severs and end users bandwidth