Ubuntu's Swap file = "dangerous"

It is more flexible because you don't have to dedicate a partition to swap and can more easily resize it as needed (you can always add more swap space as files or partitions, but shrinking the partition is more painful). It is (perhaps) more dangerous, however, if it is on the same partition as the rest of your data and files and if you have corruption in either the swap or the rest of the partition it can get destructive. Another reason applicable to older rotational non-SSD disks is that the blocks in the swap file can get fragmented and slow performance.

However, personally, I think there is no good reason to demand a swap partition any more and I have generally gone over to using swap files. Probably this will be reworded in the next update, and I thank you for your raising this issue. Unless there is a good reason for it I don't use a lot of partitions any more, mainly doing it to put non-volatile data on slower and cheaper rotational media, and things used all the time on fast SSD type media.