The Switch 'might' catch up with the XB1 but there's absolutely no way whatsoever it will catch up with the PS4 while it's still the current gen console. It might stand a chance of getting close once the PS5 has been on the market for a couple of years and people stop buying the PS4 in the numbers they are.
What I'm seeing here is a phenomenon I used to witness in a friend of mine. He would look at the PS3 numbers and constantly argue VGC is lying (couldn't entirely disagree at the time) about the sales numbers. What he was doing is looking at the sales of the PS3 and forgetting the sales of the 360. So he'd see 300k and then add that to the current figures, not realising that the 360 had also sold 200k. It was a jump of 100k but he could never compute. Another thing people do is to look at regions instead of WW sales. This is why lots of XB1 owners still can't grasp why the PS4 has outsold the XB1 by such a margin. They know the US is the biggest market for the XB1 and so they only use the US sales as an indicator for how 'well' it's selling in comparison to the PS4.
People are unwittingly doing the same here with the Switch. It won't catch the PS4 unless the PS4 stops selling and even then you can't 'assume' the Switch is going to continue to sell as it is.
The PS5 Exists.
