Keep in mind also that Intel chip have Ram integrated within it's chip power delivery, so lets say you use 25W TDP on Z2E and Intel, reality is Intel will be consuming around 3-4W less power.
So to make it fair Intel need to run at 28W while Z2E at 25W in reality
If you're waiting for the Xbox ROG Ally X, then you might be surprised to know that other handhelds already available on the market can perform just as well, if not better. A well-known YouTuber recently demonstrated this by pitting the AMD Ryzen Z1 and Z2 Extreme against the Intel Core Ultra 7 258V, essentially comparing three of the most popular handheld chips currently available at the time of writing.