I don't think Bush/Gore undermined anything.
I don't think Hillary undermined them when she told Biden not to concede under any circumstances. I don't support her or Biden's politics, but I cheered that position.
That's because in that case you had the infamous butterfly ballots in one large Florida county, where a very poor UI led to a large number of people voting for both Gore and Buchanan. You also had a large number who voted for Buchanan but for all the other offices voted for people that it was very unlikely a Buchanan supported would vote for.
For those not familiar with them, the ballots listed Bush at the top of the left page, with Gore listed second on that page. Buchanan was listed on the top of the right page, with the list on the right page vertically offset so it was like this:
------
Bush | |----------
-----| | Buchanan
Gore | |----------
-----| | McReynolds
Browne | |----------
-----| (and so on)
Nadar |
(and so on)
The ballot was wide enough that you might not realize that there were Presidential candidates on both pages.
It is very hard not to conclude that many people who wanted to vote Gore saw he was second on the left page, and so punched the second hole, and some realized their mistake and tried to correct it leading to both holes two and three punched.
That's why the challenges there did not undermine anything (other than confidence that whoever designed those ballots was competent). We had actual concrete and sound evidence that a large number of ballots did not reflect the intended vote of the voter, and there were enough of these to affect the outcome because it was an extremely close race.
The 2020 challenges so far have failed to include any concrete and sound evidence. Its all been things like that surveillance video that they say shows extra ballots being sneaked in late at night, which when you look at the whole video instead of just that short clip you see that those were ballots that had always been there--when counting stopped for the night they were put in their standard ballot storage containers, and what the clip is showing is those ballots being removed from those containers when counting resumed.
Or things like that statistical argument that was in the Texas Supreme Court filing that said there was only a one in a quadrillion chance that Trump could lead in the evening and then behind after more ballots were counted overnight, which completely overlooked that in-person ballots were counted before absentee ballots, and that Democrats were far more likely to vote absentee because of COVID than were Republicans.
That's why 2020 challenges are undermining in a way no previous election challenges were. They aren't going to force any strengthening against fraud because they are failing to point out any fraud to strengthen against.
Such proclamations come off as either "Nothing to see here" or "Lock her up" rhetoric to me. Too much, too soon.
Some of us are trying to be open-minded about the evidence being presented, while others accept the first argument that supports their bias. I think it's wiser to take the first tack.
How much more research do you do on any particular piece of evidence after some media outlet tells you that you don't need to worry about it?
[0] https://www.youtube.com/watch?v=ha7iWECm_8E [1] https://www.youtube.com/watch?v=v-nblE8ps2M
I have so far seen no reason to worry about the latter bit.