This is exactly why I stopped using page speed insights for testing. The last time I used it, which was at least a year ago, I was losing points for serving too

This is exactly why I stopped using page speed insights for testing. The last time I used it, which was at least a year ago, I was losing points for serving too large an image file size on mobile. Only problem was I use converting to webp 'on the fly' with mobile browsers. I could kind of get it if webp was an apple or ms solution but it isn't??