Open Watcom v2 installer is extremely slow on FreeDOS 1.3

This issue was first reported in the issue tracker of the Open Watcom v2 Fork on GitHub, but after some more testing, it turned out that the problem only occurred with FreeDOS, not with MS-DOS, so the installer was likely not the culprit.

To summarize, the DOS installer of Open Watcom v2 C/C++ for DOS installs extremely slowly when running on FreeDOS 1.3. It takes about an hour or more to complete, and this has been reproduced both in VirtualBox and in QEMU with KVM acceleration, on an i5 system from 2011, with an SSD. When the FreeDOS installation is replaced with MS-DOS 7.1 (the unofficial China DOS Union distribution), the installer completes within a few minutes, again in both VMs on the same host machine. In DOSBox Staging, also on the same host machine, the installation is also quick.

Link to the DOS installer executable: https://github.com/open-watcom/open-watcom-v2/releases/download/Current-build/open-watcom-2_0-c-dos.exe

I have not yet tested this on a bare metal system, but if requested, I can try to make some time for that in the weekend.

Is there a known performance difference between FreeDOS and MS-DOS in terms of file I/O?