The biggest difference between Wi-Fi 6 and Wi-Fi 6E is that 6E operates on the newly opened 6GHz spectrum. Below are the spectrums within which both standards operate:
Wi-Fi 6 = 802.11ax operates on 2.4 and 5 GHz
Wi-Fi 6e = an extension of Wi-Fi 6 operates on 2.4, 5, and now 6 GHz
As you can see from the chart above, the 6 GHz spectrum has far more channels and capacity than the 2.4 and 5 GHz spectrums combined. As you may know, the smaller the channel, the farther the data will go. The bigger the channel, the lower the range. In order for it to function properly, Wi-Fi 6E will require substantial infrastructure changes. However, when they happen, we will see an explosion in innovation especially in fields like virtual reality, IoT, robotics, and smart cities.