The Russians did interfere with the 2016 election. The Mueller Report, charge sheets and other investigations document that.
The Trump campaign did collude and attempt to collude with that interference, especially after Trump asked the Russians for assistance with missing emails in a media conference, later characterised as "a joke". This is also documented.
Collusion is not a crime though, conspiracy is. William Barr lied when he pretended there was no collusion documented in the Mueller Report when there were about 120 pages specifically dealing with collusion between the Trump campaign and Russians. Mueller pointed out that Don Jr's lack of "wilfulness" was the only reason he wasn't charged after he colluded with Russians at one meeting. Essentially, Donald Trump Jr was too dumb to know he was breaking the law by working with agents of a foreign government to interfere with a US election.
If memory serves, Mueller charged 34 people and three identities with over 200 indictments and, as a small part of that, 6 Trump campaign employees or officials were convicted. We know the Russian GRU officers, IP addresses, Russian government officials and have thousands of pages of info about how Russia attempted to subvert the 2016 election for the serial bankrupt reality TV star that they supported.
