Actually since rev 1.918 (2008/11), the GENERIC kernel does support any file-system other than FFS and NFS.On the amd64 cd image I don't see any modules.
Hmmm, I see modules on the amd64 iso image:
{17} vnconfig vnd0 release/iso/amd64cd.iso
{18} mount -t cd9660 /dev/vnd0d /mnt
{19} ls /mnt/stand/amd64/5.99.52/
modules
{20} ls /mnt/stand/amd64/5.99.52/modules/
accf_dataready compat_linux ksem scsiverbose
accf_httpready compat_linux32 layerfs secmodel_bsd44
acpiacad compat_netbsd32 lfs secmodel_overlay
acpibat compat_ossaudio mfs securelevel
acpibut coredump miiverbose smbfs
acpicpu coretemp miniroot solaris
...
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