The failure to convict Trump has probably emboldened him but the imperial presidency has been around for a long while due to the divisiveness and spinelessness of Congress and fatal flaws in the sacred but outdated Constitution. Soft-spoken Obama was a benign dictator so the military and economic establishment was happy with him and he took good care of them. If Trump were gone, we'd have Pence's Christian crusade and with his evangelical legions he'd be even harder for the Dems to beat. So, what did the impeachment effort accomplish?
Impeachment was never going to end in conviction and the self-righteous Dems always knew it. It was always meant just to get an electoral propaganda advantage for November and even that will likely backfire. Beyond that, it was useful to them to pretend that Trump was guilty of treason to not give all these weapons to the Ukraine, which they supposedly desperately need to defend themselves from those nasty Russians. No attempt to demonize the Russians should be passed up. Like Hillary, Ukraine is a victim of the Russians. (I even recall some Democrat nonsense that the Ukraine was "our" first defense against "Russian aggression" AND here.
Of course, the real loss in Ukraine would have been arms sales profits and an opportunity to expand US imperial power still further east.
More evidence of the importance of the Ukraine to neoliberal Democrats like Hillary, the architect of the 2014 so-called "revolution," aka regime change, is the recent brawl in their parliament, which was portrayed in most US media as being about Russia, when as reported in more reliable sources it was really about putting their fertile farmland on the international market, which the EU and the US are very keen on snapping up for investment purposes. Not surprisingly small farmers in Ukraine are dead against it because they are unable to pay the inflated prices for land which would surely result. While the Dems are all about Trump and Zelinsky, this is what the US stooge Zelinsky and his cohorts have been up to. So, the real Democrat-Republican struggle is over who is going to manage the neoliberal enterprise in Eastern Europe and reap its benefits a la Hunter Biden. It's simply a less obvious version of a Central American narcotrafficking turf war.
In short, time spent hand wringing over Trump is time taken from addressing the more basic issue of just how deeply and pathetically dysfunctional America is, which is not to deny that Trump can continue to do ever more incredible damage if he has more time.
If Democrats really want to challenge not just Trump but all he stands for, the first thing they need to do is jettison their right/center right pro-Wall Street, pro-neoliberal, pro-empire majority. There is little evidence that they have any intention of doing so.
The fact that people are still willing to listen to establishment Democrats is simply a reflection of their desperation for escape, which the Democrat party cannot and will never deliver. From them we can expect nothing other than the mantra that only dullards like Hillary Clinton and Joe Biden can beat Trump. It's the thesis that we need Wall Street neoliberal neocon Democrats in order to beat a racist ultranationalist idiot. Unless and until the Democrats and/or the electorate deals with its centrist/right wing majority as embodied by Biden, Klobuchar, Buttigieg, Pelosi, Schumer, Obama and DNC chair Perez etc., etc., no serious change can ever take place on all the important domestic and international issues of the day.
We cannot close without mention of the nefarious role of the media across the board, including--even especially--so called "public" radio and television with their endless fund-raisers telling us how wonderful they are. No one who is informed needs me to list any of the numerous examples I could provide of their constant service to the establishment. It's so bad and so pervasive that I cannot imagine anything short of direct action at NPR/PBS venues could bring attention to the fact that their constant pleas to their generous and willing corporate donors are the very cause of their and our demise.
While Sanders may go down, it's important that he go down fighting as he seems prepared to do. When he takes on Biden, it will be to expose the latter's service to elite power in step with the bankrupt majority of the Democratic Party. For whatever Sanders' shortcomings, he is the thin edge of the wedge that threatens to separate the Democratic establishment from its power base; hence their obsession to take him down at any cost.