Here's a good point to remember, now that the House Intelligence Report on the Ukraine scandal has been released, the Russia investigation by Robert Mueller and the Ukraine scandal are all part of the same exact thing.
Long before Trump began looking at Hunter and Joe Biden, and while he was still being investigated by Mueller, he had Rudy meeting the previous President of Ukraine and asking for an investigation into Crowdstrike as a way to rebut and kneecap whatever findings Mueller came up with. This was premeditated and long-planned.
The idea that the Mueller investigation is a "separate" matter is not accurate. The Ukraine scandal was implemented as an assault on the Mueller inquiry and is perfectly relevant to the obstruction — multiple attempts to have Mueller removed attempts to reframe the focus of his investigation to meddling in the 2020 election — are all part of the story and perfectly relevant to pointing out that this behavior is part of a larger pattern that began in 2016 when Trump was more than willing and eager to accept foreign help from Russia in that election.
With the help of the Russians, and to some extent Comey, Trump stole the 2016 election. This bottom of the Ukraine scandal is that he was attempting to finish that theft, and also steal the 2020 election by knee-capping Joe Biden just as the email investigation had knee-capped Hillary Clinton in 2016.
He did it before, he was doing it again.