IMHO, there are many people who are afraid of grooming. And by that, I mean all parts. My hubby is one of them. There is no way in heck that he'd ever ever cut their nails. It took him over a few years to even brush the dogs and even at that, he just brushes the outer coat. He doesn't brush teeth and forget clipping them. Bathing them? Forget it. He only does it IF the dog poop on himself and his fur is all yucky. He's the type who'd take the dog to a GOOD groomer.
However, for myself. I brush my dogs thoroughly probably 6x a year. They get bathed twice a year (more if necessary). I do a quick brush through maybe once a month. I clip Miko's nails every other week. I clip Koji's once a week because of his agility training. I hate when all I hear is nails on the equipment. I also clip their hair when I feel like it.
And personally, they are not suffering. Shelties don't need to be brushed once a day. I have utterly slacked on Miko's coat over the years due to working FT and going to school FT and having no money, etc, etc, etc....and he's fine. I chose not to take him to a groomers since I only heard bad things, and I figured he was so calm I could do it myself. Yes, I have chopped his hair badly at times, and he still loves me and puts up with it.
I think a person should care for their dog. Be reasonable. If the dog comes inside, maybe wipe off it's muddy paws, or shoot them down with water. If the dog is overly dirty, wash it. Brush them or at least keep an eye on knots (that's what I do when I get lazy). I'm not perfect and don't pretend that I'm not lazy when it comes to grooming my dogs. It takes every ounce I have to brush my own teeth.....imagine me brushing theirs. Thank gawd for chews.
Lastly, Shelties don't need to live in the Shetland climate. And if they do, isn't that a lot higher than anything in the US? I live in SoCal. It can get hot here. No biggie. Besides, my boys seem to love to sunbathe. And that can get extremely hot. They're made for that too. Their coat protects them from the heat and the cold. As long as they're not shaved.
Sigh. People do what they want. They dye poodles pink, shave chow's, give funny haircuts to any dog. People paint their dogs toenails, dress them up in interesting outfits. What can we do about it? I figure, as long as the dog is well-cared for and loved, who cares if it's shaved? I'd just chalk shaving to cool a dog down ignorance. Most people think they're hot. But their coat is what protects them from the sun/heat.
Just my two cents. I'll get off my soapbox now.