Watergate was a seminal moment in US politics, and only Ford's decision to pardon Nixon prevented him from being impeached. Nixon was not being charged with treason, or with an attempt at overthrowing an election, since there was not enough evidence that he was aware of what the group that broke into the DNC's campaign HQ was doing. It's difficult to say if Nixon got off easy or not; I don't think he would have served any prison time, and the damage to his reputation may have been worse for having the process cut short by Ford.
Trump, in spite of his rhetoric at the time (and frequent complaints about the election since), will likely not face any charges either. And the desire to get back at him is probably a very distant second to the realization that any action taken against him will set a precedent, and his reputation is pretty much set at this point, for better or worse. There are too few politicians who want to set an example --no matter how badly they'd like to hurt Trump-- that might be used against them in the future.
As for the rioters, 862 of them have been charged, with more being sought:
https://www.insider.com/all-the-us-capitol-pro-trump-riot-arrests-charges-names-2021-1
Only 11 have been charged with seditious conspiracy, and that case is considered challenging:
https://www.businessinsider.com/doj-uphill-battle-prove-sedition-charges-capitol-riot-probe-2022-1
The hope right now is that the spectacle will draw enough attention and garner enough anger to affect the November mid-terms and possibly prevent Republicans from making large gains. But the number of people who have watched the hearings is about the same as generally watch the nightly news. A good level of interest, but not what I expect they were hoping for.
Democrats want to prevent or soften the impact of the mid-term elections, since the GOP will almost certainly hold hearings of their own (and open up their own investigations into 1/6/21) if they get majorities in one or both congressional houses. The only thing that may prevent that show from going on is that there are so many other hearings that they want to hold (and on much more politically useful topics) and only two years before the next Presidential election. They would love for people to spend less time hearing about Donald Trump and more time hearing about Hunter Biden (one of the few people who makes Trump almost seem like a moral person).
