They are. Look at the total numbers at the end for PS4 and Switch. It shows around 94M for PS4 and 32M for Switch at the end of 2018. Those were shipment numbers.
The link says it takes numbers "From the CESA report, sell-through data from 2012 to 2018 in many countries" but this doesn't mean all the numbers combined are sell-through. If the total amount of sales showed there put PS4 at 94M and Switch at 32M at the end of 2018 they're definitively shipment numbers.
I can totally guarantee you that PS4 did not "sel to consumersl" 900k in 2014 in Spain like it's showing that graph. Those has to be shipment numbers in case of being true.
Its sell through, USA is based on NPD, Japan based on Media Create/Famitsu and Europe based on Gfk while RotW are estimates which explains the slight discrepancies.
When the herd loses its way, the shepard must kill the bull that leads them astray.