This was not a violation of law that is an assault against our system of government. Holding up the money to Ukraine not only was a violation of law but it was done to interfere in the upcoming 2020 election.
That's the difference in a crime vs a crime that is impeachable.
Driving 5 mph over the speed limit vs 50 mph over the limit are both crimes but handled VERY differently
Even if what Trump did broke zero laws he should still be impeached for it. He tried to rig his own re-election!