LeCun - ML is biased when datasets are biased. But unlike deploying to real world problems, I don't see any ethical obligation to use "unbiased" datasets for pure research or tinkering with models.
Gebru - This is wrong, this is hurtful to marginalized people and you need to listen to them. Watch my tutorial for an explanation.
Headlines from tutorial (that Gebru didn't even link herself): The CV community is largely homogenous and has very few black people. Here's a bunch of startups that purport to use CV to predict IQ, hiring, etc. Marginalized people don't work on these platforms and there's no legal vetting for fairness before these platforms are deployed. Facial analysis has the highest rate of inaccuracy (gender classification) on fair-skinned men (?) and dark-skinned women. Datasets are usually white/male. Most object detection models are biased towards Western concepts (e.g. marriage). Crash test dummies are representative of males, so women and children are overrepresented in car crash injuries. Nearest neighbor image search is a unfair because of automation bias and surveillance bias. China is using face detection for surveilling ethnic minorities. Amazon's face recognition sold to police had the same biases (greater difficulty distinguishing between black women).
Now, I largely agree with what Gebru said in the tutorial. So does LeCun, who explicitly agreed a number of times that biased datasets/models should never be used for deployed solutions.
But it's a huge leap in logic to then demand that every research dataset be "unbiased". It's like criticizing someone for using exclusively male Lego figures to storyboard a movie shoot, or if I attacked a Chinese researcher because they only used Chinese faces to train a generative model, and none the outputs looked anything like me.
That being said, I'm open to being convinced if she had made any effort to show/prove that "use of biased datasets in research" is correlated with "biased outcomes in real world production deployments". But she didn't, which is why her criticism of LeCun smacks of cheap point-scoring rather than genuine debate (a criticism I made of Twitter generally the last time this topic came up).