No information useful to the Trump campaign was provided by the Russian lawyer.  This fact means nothing.
Trump, Jr. was eager ("I love it") to take the meeting even after being told "This is obviously very high level and sensitive information but is part of Russia and its government's support for Mr. Trump – helped along by Aras and Emin."  This fact means everything.
A Trump campaign insider willing to meet with Russian nationals + Russian nationals willing to provide information damaging to Clinton + hope on both sides of aiding the Trump campaign = collusion.
There is no other way to explain or defend this.