The emails are highly embarrassing and politically damaging, but as usual, the media and other Trump opponents are overstating the case. The media overstating the case and popping the champagne corks are probably the best things Trump Jr. and the Trump administration have going for them.
The emails show no actual evidence of collusion or illegality. There is nothing indicating the information to be offered was stolen or otherwise improperly obtained, or that other than being willing to listen, the Trump campaign was involved in how the information was obtained. To the contrary, the promised information was official records and information.
This also took place prior to the hack of the DNC being publicly known, so there was no reason to suspect that this was hacked information. Notice how the narrative has changed from the Trump campaign colluding with the Russians to hack the election to the Trump campaign being willing to have a meeting with someone who may have damaging oppo research.
And of course, there was no there there. Theres no indication any information actually existed.