I'll say it again: We can now see that FindFirst and FindNext were not bad ideas after all.
I typed a lot so i can be better corrected, not because I understand what is going on.
At the time people looked down on it mostly because everybody else did it differently and DOS looked like a toy OS compared to more advanced ones.
Of course, my comment is kind of a joke. There many advantages on more advanced ways to list files on a directory. Not having to make one syscall for every file is just one.