Totally unsurprising if you've ever worked with Oracle. The layers upon layers of legacy cruft are plainly visible even in simple things like the GUI installers.
I remember an oracle forms product based product I helped develop to install on end users pc's required several oracle products installing - which meant 14 or 15 Floppy disks to be used in the right order.
I mean, PostgreSQL can trace its roots back to 1982's INGRES ... and UNIX started in 1969.
There are quite a few very old projects that don't have the same level of cruft as Oracle; it epitomises a Sales Division driven culture.
How many of those switches (that now need to be supported and tested) are because some functionality was promised to a large contract, and so it just had to be done? I would wager a good number.
