What people who go after Trump is prove collusion.
Trump had a press conference calling on the Russians to hack into or have already hacked into Clinton’s email server and give the United States the emails. That is Trump -Russian collusion. Just because Trump does it in a press conference with millions listening or a private phone conversation.
Trump fired Comey because of the Trump -Russian collusion investigation, and Trump admitted it to Lester Holt on an interview watched by millions. Just because millions watched it, doesn’t make it not true.
Maybe Trump thinks that if he does it in private, it matters, but if he admits it to millions it doesn’t matter. The only thing that matters is that more people are in on the admission of guilt is millions hear the guilty persons testimony.