What does that have to do with respect for receiving device or connection speed?

If the respect was for the receiving device or connection speed, the metric used to determine priority of results would be size of payload / speed of delivery, rather than if the technology / hosting was google-owned.

As far as I recall they fixed that, now the problem is that they the measure for speed they use does some weird tricks around partial loads; as long as you display _something_ soon they are happy and the fact that a page might be useless for many seconds is weighted less

That matches with human psychology of perception, IIUC.

Yes, I understand why they would want to do it. But it also mean that I am staring at a unusable page...

But the alternative is you'd be staring at a useragent-provided crawler for N seconds to get to a usable page, right?