Here are some accurate comparisons.
Neither men get/got credit they deserve for policy successes, and both have/had rabid ideologues who live/lived to take them down.
Both Donald Trump and Richard Nixon followed Democratic presidents who were handled by media with kid gloves. They could do no wrong. Nixon's first opponent truly stole a presidential election. Trump's tried but failed, then projected.
I could go on. But these Watergate comparisons are beyond stale, a lot like those who are still trying to milk it.