I think it's just realism with the basic spec batteries they are probably using. They often only perform well for about 300 charges before starting to die under load on steep hills and cutting out. They aren't going to be treated well after all, casual cycling users will slog the motors on hills and not pedal much if they don't need to. So to avoid the aggro of complaints, replacing them at 300 charges makes sense.
Landfill no doubt there's still no good lithium recycling facility apart from a German small scale effort that can only recover 50%.
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