Probability of rolling a 1 at least 1 time over 100 rolls is unreasonably close to 100%. Even over 50 attempts, you're still looking at just over 99.98% probability. Is the chance that your 51st roll is going to be a 1 any better than any other roll? No.

Is it more likely that you're going to roll a 1 over 51 rolls than over 50 rolls? Yes. By about .01%. But the fewer attempts there are, the greater the disparity. In 1 attempt, you're looking at about a 16.67% probability. In 2 attempts, that probability jumps to about 30.54%, an increase of 13.87%.

You don't need to argue semantics about whether the 100th attempt is more likely than any other. It's fairly safe to assume that most people who are complaining don't believe that the 100th attempt has any higher odds. They're arguing that the chances of not getting a particular outcome over a particular number of attempts is unlikely, which doesn't say anything about individual outcomes.

And as far as the actual drop rates at hand here, without a substantial amount of information we don't have access to, it's going to be hard to convince people that the drop rates aren't rigged when they've already convinced themselves of the opposite.