Likely because she’s a fake profile employed by the dating app provider to make it look like there are tons of available women on the platform.

This way the (male) customers think they can’t find anyone on the platform because they are not attractive (too short) and not because the platform is filled with bots.

And since height is a metric that’s close to impossible to change, there’s no way for the customer to improve and then figure out that the profiles are fake.