In short the main advantages to you as the publisher are Time and Money. Not to mention the ease of having everything organised in one place.
There are many plugins and tools out there that can increase site speed, but many cost money (either one time purchases or subscription fees), on top of this they require tedious work to configure for your site.
With Leap, you can instantly implement best practices for website speed: Critical CSS, Lazy Load Images, Next-Gen Image Formats, Resize Images, Pre-connect Origins, Script Delay, Lazy Load Iframes, and more, all in the matter of a few minutes.
It's a one-stop shop for speed. Instead of having separate plugins or scripts to minify CSS, remove unused CSS, etc. Leap has all those features and more baked into a single tool that is designed to work as easy as “on and off”. There is no other tool on the web that can replicate all of this on sites with ads.
This is a benefit to both the publisher’s day-to-day and the objective speed of the site. It is an easier and faster process to test different Leap optimizations than it would be to try different plugins. And the more plugins you have, the slower your site's LCP becomes, since plugins have to make call-backs to the origin server to execute.