In general, trends can be somewhat unfortunate, as many follow trends to fit in but may not have much thought or consideration for what they are doing beyond that. My horses go barefoot when it is appropriate. Until they are three years old, they are unshod, and often when they are on summer pasture. We live in Norway with snow and ice, and to avoid injuries in the winter, we rely on training horses having shoes with studs and hoof-grip. In the summer months, the hooves wear down a lot due to stones and gravel on the roads and paths here, which is why we use flat shoes in the summer. Our horses are trained six days a week; if they were only trained sporadically or once or twice a week, then boots might be relevant. But in our situation with many horses, a lot of activity, and rough terrain outdoors, we avoid problems like soreness and poor well-being by using shoes. Lastly, we shoe our horses every seven weeks by a very skilled farrier. If we did not have access to a good farrier, the assessment would probably be somewhat different. Poor shoeing is much worse than going barefoot. So under certain circumstances, such as young horses, soft ground, little training, or a less skilled farrier, I am absolutely positive about barefoot horsekeeping.

As long as you see the whole situation and make an assessment based on that, keeping the horse's best interests in mind, it doesn't matter much whether they are shod or barefoot—just as long as it works :)