both parties do this -- specifically, the one and only green party assembly member in California 1990s was doxxed and infiltrated, while getting congratulatory letters from GOP reps.
The criticism is "this is a bad thing the current Republican Party is doing right now in a widespread fashion"; "there are past examples of the Democrats doing this" is not a defense. If it's a bad thing that we should try to stop any party from doing, then right now that means trying to stop the Republicans from doing it.
The bad thing we are talking about right now is the Republican Party trying to engineer a de facto one-party state through gerrymandering, court stacking, and just taking advantage of the ever-increasing "handicap" both the Electoral College and the two-Senators-per-state apportionment give Republicans due to the rural vs. urban alignment between the two parties. The argument "yes, but the Democrats would do the same thing if they were in the position to" may be true, but it's not a reason not to do something about the Republicans actually doing it right now.
So the Democratic Party controls both houses of Congress and the White House, and they're trying to pass bills to give the Attorney General control over all federal elections in the country, but you say that it's "the Republican Party trying to engineer a de facto one-party state."
The big difference is that the Democratic bills all are focused on making sure that more eligible voters can and will get out to vote. They are not picking out groups and trying to discourage those from voting, which many of the Republican attempts at the state level are pretty nakedly doing (e.g.: limiting things that are only done in urban areas, killing Sunday voting because "souls to the polls" drives were so successful in areas that voted Democratic, etc).
So, yes. It is very much not the same thing. The Republican efforts behind a "voting security" banner, when Republicans in charge of the 2020 vote called it "the most secure ever", is nakedly trying to disenfranchise the vote to tip power in their favor despite the majority of eligible voters going the other way.
