All my lenses just doubled in length ....

"this is just interpolation/cropping/upsampling".

What else did you think it was? You thought Sony was making some voodoo magic to increase the range of your lens physically?

All they are showing is a better way of doing it with better results and to my eyes it does look much better. Is it going to be good for everyone or every occasion? Of course not, but it is a nice thing to have when you need it.

I will be testing it at 1.7x vs my TC at 1.7 today as well to see how it compares to it. Do I expect it to beat my sony TC? No, but maybe it wont be too far off...we shall see.

The images in the OP , look very nice at normal sizes so I think that alone shows it is viable option in some cases.

Regards