There are 2 sorts of ignorance. Incidental and willful. Incidental can be fixed easily, with more information. Willful only look to support their pre-decided views, and so are far harder to change.

Before the internet became a big thing, both were common on topics. We were forced to rely on what we were told. This lead to a lot of incidental ignorance. The internet made it easy to fix this.

The end result is the ratio has changed. It used to be, say 80% incidental, and 20% willful. Now 90% of the incidental is mostly fixed. So it's 29% incidental, 71% willful. And so looks a lot worse to casual observation.

The Grandma seems the incidental type. Going to a game gave her the information to update her views.

Also to note, the numbers here were pulled from my arse for example purposes only. Actual ratios may vary.