Nvidia reduced the baseline minimum TDP of Max-Q Turing GPUs when compared to last generation Max-Q Pascal GPUs. The result is that more laptops can now run the RTX 2080 Max-Q GPU, but the performance gap between it and the RTX 2070 Max-Q can be surprisingly narrow.
https://www.notebookcheck.net/The-fastest-GeForce-RTX-2070-Max-Q-laptop-is-just-7-percent-behind-the-slowest-RTX-2080-Max-Q-laptop.413234.0.html