@diesel12, nothing has changed with the actual compression methods used in free mode, or in paid mode, for quite some time. Although the tools get updated from time to time, it’s generally for bugfixes, as the compression gains are already pretty well maxed out.
The percentages are designed to show you how much you’re missing out on by not using Premium compression, as the average with Pixel Perfect (lossless) is 7-10%, whereas the Premium is 45% and Premium Plus is over 55% on average (both lossy, but what some call “visually lossless”).
That said, you’re still quite welcome to use the free mode, and I have no intention of changing that ??