When I tried out my current horse, he was owned by an experienced horsewoman and sometime endurance rider who had opted to go both barefoot and vaccine free.
I asked her to canter him on a nice section of trail with excellent footing and she said, "Oh, I wouldn't want to canter him very much, he's barefoot you know, and I don't want to sore him."
Of course my first thought was that she was hiding something, but he vetted fine, and I bought him. Being a less open-minded horse owner, I had him vaccinated and shod.
He's an absolutely tough little mountain goat of a horse and is scrambling up and down our steep rocky trails like an equine ATV.
I have no ax to grind re barefoot horses if they can go where I need to ride and I know there are those who have demonstrated that some can, but if being barefoot prevents me riding on the only trails I have available, then it is not for me.