Your friend's husband isn't the one giving birth, so it's not his decision.
That said, I have had both a C-section and a vaginal birth, and I personally found the vaginal birth much easier.
Admittedly, the C-section was following a failed induction, so I did experience contraction pain for a few hours before I had an epidural, and I was pretty exhausted by the time I had the C-section. I also had an epidural when I gave birth vaginally, which meant I only felt the contractions whilst in early labour and not for what probably would have been the most painful part. So if I were comparing a nice calm ELCS after a decent night's sleep against a difficult vaginal birth without pain relief, I would probably feel differently. But for me personally, the vaginal birth with the epidural once things started to heat up was a much more enjoyable experience.
If your friend is worried about pain, she should consider getting a lightly dosed epidural once she is in active labour. The women I know who have done this have had pretty positive experiences. If having an ELCS is what she really wants, she is of course entitled to request one. But it is not pain free. The pain comes afterwards, when the incision is healing.
Either way, your friend's husband needs to butt out. He needs to understand that C-sections are a perfectly valid way of giving birth, and in some situations they are life saving. I really hope he is not going to be unsupportive if your friend decides to attempt a vaginal birth and then ends up having to have a C-section anyway for medical reasons, which could easily happen.