It’s really useless. It seems to be a little bit faster the next day after the installation. The speed measured by Google, after 3 days, is getting slower and slower than before the installation.
Hey there -- sorry you didn't notice any speed increase with Superspeed!
Sadly, tools like Google's PageSpeed and Lighthouse don't capture the speed improvements that Superspeed makes because they test only the speed of the first page load, not the subsequent ones. Superspeed only speeds up the subsequent pageloads. If you have a Real User Monitoring tool available, it should show a significant speedup in all the page loads after the first one.
Also, Superspeed loads as one of the very last things on your shop, so it shouldn't affect the speed of the first page load either. I'd check to make sure it's actually Superspeed slowing your store down and not something else!