I am certainly no Trump apologist, but threatening to leave NATO was a classic "art of the deal" tactic to get some NATO countries to pay their fair/agreed upon share.

If Trump really is Putin-friendly, then Putin made a massive mistake by delaying his major military actions in Ukraine until Biden was in office.

I have no real proof of this but I suspect if Putin did delay his actions until Trump was out of office, it was because Trump was such a wild card that Putin might think that he could try to nuke the Kremlin if he didn't like what was going on in ukraine.