I would think the 2nd is more likely to rely entirely on one or two thin laminations in each direction. The classic joint would potentially have more than one lamination in the thinnest part (albeit the same thin part)

I think the classic method probably by design holds up to the stresses of shacking and bumping the machine a bit better than the more squared method. Really the internal brackets are the best solution, as it connects both planes at a larger point, and transfers more of the stress of shifting the machine to the legs as the plates are unified by the bolts.

That's all my best 'guess', but maybe some has tested.

What's a surprise here, is I've only read one instance of anyone reporting this to the manufacturer and the response was thanks let us look into it. Call it in and see what they do. Maybe they might do better than expected, taking lessons from the ghosting issues. If not, then there's plenty to moan about on all sides and fuel to keep the pitchforks glowing all the way to Chicago.