Anecdotes are data. Quite literally. Each is one data point. A data point is not a conclusion. To draw valid conclusions you need a large body of data. But each anecdote is, quite literally, a single data point.

A grabber sentence is a literary concept that includes a rhetorical generalization used as a pathway into argument.

That part worked, pretty predictably, but it doesn’t seem like you read the argument. Hm.