The BBC asks "do people become more prejudiced as they age?"

No.

Psychologists used to believe that greater prejudice among older adults was due to the fact that older people grew up in less egalitarian times. In contrast to this view, we have gathered evidence that normal changes to the brain in late adulthood can lead to greater prejudice among older adults.

There are certainly normal changes to the brain. We call that "life".

Old people have experienced more of life than when they're young, so they have more facts at their disposal to make judgements.

This isn't prejudice. It's postjudice. So the BBC approach of venerating the young and disapproving of the attitudes of older generations is precisely the wrong way around.