Paraphrasing my doctor: infections have evolved to the point the fever isn’t effectively contributing to fighting the infection, but we never evolved to stop making the fever. Since it doesn’t do us any good, we might as well be as comfortable as possible while our immune system does it’s part.
It’s a 32 year old format that makes pictures worse in order to save space. A lot changes in the tech works in 30 years. While there may be nothing inherently wrong with it, there’s far better image encoding algorithms these days that can store images in less space without reducing the quality as much.