An example that 'some indicator in some situation does not change some people's vote', does not generalize to 'indicator never changes anybody's vote in any situation'. People said they were voting based on the economy, and it drove votes that also ran directly contrary to this identity stuff. For instance, Trump won Hispanic males by 10 point margin.

The point about online bubbles is that what you read online isn't representative sample of what people in the real world are like. People who post online are a vocal minority that disproportionately often hold fringe views that typically become even more fringe over time due to the radicalizing effect of the echo chambers that most prefer to post in.