Would it be good for the country to impeach Trump for his Ukraine phone call, having not impeached his recent predecessors for graver offenses? If raising the standards means the standards would be kept there, perhaps yes. I believe Ramesh Ponnuru would keep the standards there. Would others? I also suspect that while Ponnuru might quibble with some of my examples of presidential abuses before, he generally agrees that modern presidents have been getting away with impeachable offenses.
My next question: Why isn’t Trump getting away with his? I suspect the reason is similar to the reason that Andrew Johnson was impeached. Clinton too. Offenses to the Constitution are routinely tolerated in presidents. but Trump’s Democratic opponents and Republican critics find themselves literally disgusted by him. I cannot prove, but I suspect, that it is this more visceral disgust — one that predated the release of the rough transcript of the Ukraine phone call — that is driving impeachment. Finding a tax-evasion charge on Al Capone may be expedient for imprisoning him. But finding a technically abusive request that was not carried out in order to effect the already desired impeachment is something less than constitutional hygiene.