It takes less download but more CPU to unpack it so the loading time depends on your connection and hardware. In extreme cases it may be worse than png.
I noticed this when mass converting images for my site. They'd download super quick, but then take forever to render on my ancient Macbook
Ended up using webp for the first image since it was rendered super fast, and a mix of jpeg/webp/avif for the rest (hidden in a carousel), depending on filesize and how legible text was in each image