As Ilbranteloth pointed out, that's simply untrue. I only fudge when the bad luck happens to such an extreme that it breaks the game math and will kill the party. I then fudge only to nudge the party's chances back into the acceptable range of probability. That range still includes the possibility of PC death or TPK, so if they win, they have still earned that high five.
A recent event in our current game kinda made me think about this thread. Our 6th level party was facing an enemy group, including a pair of trolls. One of the trolls had disadvantage on attacks and then proceeded to hit the monk three straight times anyway. A very low percentage event. Thing is, even with three hits, all he did was hurt the 6th level monk, nothing too serious. Dropped the monk out of about half of his HP.
This got me to thinking, what if that troll had critted three straight times? Well, other than probably dropping the monk to zero HP, nothing. It would be virtually impossible for the troll to outright kill the monk (barring hitting him after he's down). But, that's a CR 5 troll vs a 6th level PC. He
shouldn't be able to outright kill that PC. That's exactly in line with encounter design and CR expectations.
So, a 1 in 8000 event (something that is rare enough that it should qualify for Maxperson's criteria of a fudgeable die roll series) would almost never be fudged because there is no need.
But, let's jack things up a bit - since that's generally what happens in a Very Deadly (or more) encounter - we use monsters whose CR is greater than the PC level. So, let's go with a CR 9 brute of a critter... Lessee... CR 9 Fire Giant. That's a nicely upgraded troll. Big brute critter without a lot of extra magic attacks. Three straight crits from the Fire Giant would outright kill a 6th level monk. Actually, since our Fire Giant only has two attacks, two straight crits still has a pretty good chance of killing the monk. So, a much, much higher chance event than 3 straight crits form the troll, results in a dead PC.
Which, IMO, greatly increases the need to fudge. The point of fudging is to protect the party from the extremes in the die rolls right? Well, part of the reason fudging is necessary is down to play style and encounter design. By jacking up the difficulty by using bigger critters, the pressure to fudge becomes quite a lot greater. In the troll encounter, there would almost certainly be no need to fudge. Even a one in a campaign bit of luck - 3 straight crits on the same target - doesn't need any intervention from the DM.
I wonder if this goes some distance to explaining the different approaches. Those that don't fudge, at a guess, probably hew closer to baseline game expectations, and those that do fudge tend to wander further afield when creating encounters.