I used to think this and then I saw how well webp reduced my website's bandwidth costs compared to optimized jpg or png. I felt a bit left behind at that moment, like I should have been paying attention to these great improvements over the years.
Which I think it might be one of the reasons why Instagram still uses JPG for their images. The rule of thumb is that if your product is picture quality sensitive (like photos in IG) then use JPG, if not then WebP is fine since the compression is higher.