QFN packages would not benefit much from this (you cannot make much more than a basic breakout board, whose same purpose is better fulfilled with one of those SMD adapters from aliexpress)
And regarding high-speed digital buses... are we being genuine here? Just the fact that you cannot have meaningful design over ground return paths with this thing makes any moderately fast digital link unfeasible. Best you'll be able to manage is regular speed SPI (which also does not need a board like this), you can forget about RGMII, ULPI, LVDS, MIPI, SLVS-EC, or anything else for that matter.
And regarding high-speed digital buses... are we being genuine here? Just the fact that you cannot have meaningful design over ground return paths with this thing makes any moderately fast digital link unfeasible. Best you'll be able to manage is regular speed SPI (which also does not need a board like this), you can forget about RGMII, ULPI, LVDS, MIPI, SLVS-EC, or anything else for that matter.