My question has emerged, because of the following similarities between the metric an observer experiences in the Schwartzschild space being under the Schwartzschild radius and an observer in the de Sitter space:
Both observe an event horizon covering the whole sky. All paths lead to the event horizon.
The distance to the event horizon shrinks over time, as well as its area.
The event horizon emits radiation with the temperature inversely proportional to its radius.
Both observers experience tidal ripping forces.
All geodesics end on the future timelike singularity, there is no path to escape.
If in fact both metrics are different, in what ways can the observer determine, in which one of the two he is situated?