The problem is that he was eager to receive such information from a source claimed to be the Russian government. The optics are that Russia was meddling in the election to help Trump.
Yes, but nobody was talking about that in early June last year. The DNC emails weren't released until late July. They refused Homeland and FBI assistance in ascertaining responsibility. In late September, Hillary famously lamented 'why am I not 50 points ahead?' The announcement about Russian involvement didn't come until early October. At that time, all they could say was 'they were confident,' but they couldn't really prove it. IMO, panic was setting in because the race was still close to those who had the behind the scenes data. They needed to push the Russia narrative to open ground.
Besides, what he had been told was they had information on illegal contributions, which are serious crimes, if it had been true - not just 'political dirt.' As it turned out, the meeting topic was adoption legislation. Junior is only guilty of being a naïve dupe.