If you are using page builders like Elementor, Beaver Builder…etc you will be able to gain a significant boost in page speed once you switch to Gutenberrg. I did and are happy I made the switch.

2 stars because I use it only on my homepage. And honestly, I don’t like the experience. Too many clicks just to make a simple change or addition. In some cases the block features are pretty primitive, unless you supplement with some premium block plugins. So it’s not really free to some extend.