The idea that “your data is yours” has become part of the digital common sense.

Platforms emphasise transparency. They offer download tools. Privacy dashboards are more visible than ever. The message is reassuring: you are in control.

I wanted to test that assumption in a simple way.

So I tried to leave Facebook properly. Not by simply deleting my account, but by downloading my data to see whether it was truly portable. Could I reuse it? Could I rebuild elsewhere? Could I meaningfully take it with me?

The experience was revealing.