What is an example to understand that having multiple data files helps with latch pages in parallel?

> You will always benefit from multiple data files, because then SQL > Server is able to latch multiple system pages in parallel in the > Buffer Pool. Link: https://www.sqlpassion.at/archive/2016/08/29/files-and-file-groups-in-sql-server/ I currently have one data file. I'm exploring the use case of adding a new data file, or increasing the size of an existing data file. Given that my IO subsystem (Data drive) can withstand high IOPS, I understand that there is no performance improvement whether I have one or more data files. And because there is no limit to how many threads can use the data file for read/write in parallel, SQL server must allow parallel latch of pages. So then, why does the author say that - having multiple data files gives the Server ability latch multiple system pages in parallel in the Buffer Pool. Why would this not be possible with single data file?