Is Legacy content/backwards compatibility important for a console's success?

[IcaroRibeiro]

Shiken said:

Is it important for a console's success? No...

Can it help give incentive? Yes...

Is it important for game preservation and should people care more about it? YES!!!

I don't understand this argument 

In 2021 there isn't any risk of any published game disappearing. They don't need preservation, they are preserved already unless you manage to delete every file stored in any storage in the world