You can't really bring non binding, non serious agreements that were never put in writing or ratified and that all parties declared no longer relevant back from the dead and feign moral outrage. That's ridiculous.
U.S. was strong for a long time. It did whatever it liked.
Now Russia restored some of its strength to the point it can show others that sometimes you have to listen to when a bear warns you (quite calmly and nicely first).
That way the other party knows that this agreement has some backing and staying power.
Not some dude spouting some ideas to counterparts during very very turbulent times.
Many people (even Americans) claim U.S. is not a democracy. Every country has corruption to some degree. The only backing and staying power there is - is the force a country has and its willingness to use it to defend something.