That article leaves out the one and only solid reason for impeachment: war crimes.
It was impossible for Trump to have obstructed justice. I've said it over and over. There was no justice in any of Russiagate. It was a totally made up farce from the very start. Everyone who had any brains and knowledge about Trump and Putin at all knew it for sure. Most of us said it too.
There were never sufficient grounds for investigating. The investigations that took place were completely crass politics.
Trump did the Constitution a disservice by not shutting the investigations down. He allowed a moronic, idiotic precedent to be established.
Let's pray the next President won't be so stupid if he or she is attacked in a like manner.