The reason why Elon Mush is wrong about us being in a simulation

Few days ago, at a tech conference in California, the great visionary Elon Musk made quite a statement in response to an interesting philosophical question from the audience about our civilization living in a simulation. Musk's key conclusion to the response was that "There is only a'one in billions' chance that we're not living in a computer simulation". How the heck did he get to this point? The simplified schema of Musk's reasoning is the following: since we have been making substantial improvements in technology (and especially in video-games) in the last 40 years, at this rate (or even at a 1000-times slower rate) we will be able to reach relatively soon advances in such technologies which will not allow to distinguish anymore between reality and virtual (or digital) reality. Hence, it is much more likely that we are already living in this future and in one of these virtual realities, implying also that someone "got there before us".