The so-called President is unfit for the office of President and THAT is why he should be removed from office. If the bar is that it must be proven that he committed a crime, colluded with the Russians, obstructed justice or has breached the emoluments clause in the Constitution and those crimes cannot be proven to the satisfaction of willfully ignorant Republican congresspersons, we will continue to have as President someone who: lies constantly; is a misogynist who has bragged about committing sexual assault; is a religious bigot towards Muslims, atheists and others; hallucinates, fabricates; bullies; is ignorant; is totally unaware of his own limitations; has numerous conflicts of interests; breaks BIG promises then lies about breaking them; and, oh yes, is the most perfect example of narcissism in the history of the planet. In other words, even if he is not impeached for a high crime and misdemeanor, he remains unfit to be President.
The obstruction of justice and the emoluments clause are his biggest criminal problems but if he had not threatened and then fired Comey and was not milking his position for personal profit, would he be otherwise fit? The answer is no. Suppose, in an alternative reality, Comey had been a lackey who did the so-called President's bidding and did not get fired, would the so-called President then be fit? The answer is no.
He is simply mentally unfit for the job of being President. This is not about politics since his replacement, VP Pence, is a more classic Republican than he is. The 25th Amendment exists as the remedy when the President is unfit but it would take guts from VP Pence, guts the VP has never displayed. But this is what needs to happen for the good of the country. It's not a good idea to have a mentally unfit President no matter what his politics are or what the politics of his replacement would be.