I could even see tech-stealing from flipping planets being more likely than with an invasion.
On first glance, I heartily agree with this take.
Conversely, with an imminent successful military invasion, you would probably have the defenders destroying databanks and information in an attempt to give the conquerors as little as possible.
This line actually made me imagine possible objections from the "balance" and/or conquest-win fans.
I have no idea if the code already works this way, but it seems to me that if you have a fairly high intel rating against an enemy, an invasion should have as good or better chances for yielding a tech than a culture flip. Also, if the civ losing a world to you in a flip has high intel on you, their on-planet agents should have a good chance of foiling any efforts to "share" a tech with the new bosses.
p.s. I've barely ever chosen Evil and wonder how common it is to choose that alignment and *not* go for a conquest win?