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.
The post I replied to said "If I'm doing vias, I'm nearly finished with prototyping". You're not if you're using a QFN switcher which needs heat dissipation via the center pad. There's lots of cases of prototyping where vias would be handy.
> you cannot make much more than a basic breakout board
Except, you know, all the supporting circuitry, connectors, maybe microcontroller and JTAG header which could be put on instead of bodged together with random wires -- exactly the problem this is targeted to solve.
> Just the fact that you cannot have meaningful design over ground return paths with this thing makes any moderately fast digital link unfeasible.
You can with a 4-layer version, which is brought up in the video as one of the obvious improvements to make/try, and you would need/want the vias at least to route the other signals around your high-speed traces.
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.