A few things to keep in mind —
First, only a minority of Americans considered Watergate to be a problem. Until evidence showed up pointing to Nixon’s guilt. At that point, a majority of Americans supported impeachment for the first time. But until that point, a majority of Americans were willing to give him the benefit of the doubt.
Second, it’s not unusual for the party out of power to be considered to be standing against the opposition more than for standing for something. The same thing happens to the Republicans when they are out of power. Perhaps you completely forgot about the Obama years, when the only thing Republicans in Congress did was to obstruct everything Obama tried to do? And Americans knew it, too. The Democrats still stand for everything they’ve always stood for. It’s just that they don’t have much of a voice these days. That will change.
Third, it’s true that Trump supporters are pretty unshakable. Trump was probably right when he claimed that he could shoot somebody on Fifth Avenue in broad daylight and not lose any support. However, Trump still has the poorest approval rating of any President at this point into his presidency ever since polling began. What does this say about Trump supporters? It says they’re pretty loyal, of course. Let’s see how loyal they continue to be.
Fourth, if the Mueller investigation turns up nothing (and the FBI investigation turns up nothing as well), Trump will emerge with renewed support, and so will the GOP. However, if these investigations do turn up anything incriminating, Trump and his team are toast — just as Nixon was. And the GOP will get sucked down with him. It will be interesting to see how loyal the Trump supporters are then.
And one more thing — you talk about the “pro-business” election results. By that, I assume you mean “pro-Republican” results. Do I have to remind you that more people voted against Trump than voted for him?