Yes, I've seen MB's hacked Noisy Magnet. I refrained from comment.
I've done both.
I've rebuilt milsurps that were just too far gone for me to restore back to military condition, making them into precision and sporting rifles, the latter along the lines of R.F. Sedgley and the lovely commercial sporting Mausers as delivered from Oberndorf. They aren't worth anything near what a pristine Mauser or Springfield would bring, but they have their place in my collection.
I've also restored milsurps that Bubba hacksawed and Dremeled into abominations, but the bolt and receiver were still unmolested, giving me something to work with. My 1903A4 came to me as a hacked "deer rifle", albeit with 18" barrel and crudely hacksawed stock. I thought about passing on the project, until I saw the offset "Z"-prefix serial on the receiver. That warranted my efforts, right there. Truthfully, I've done more Bubba restoration jobs than the other way around, by a large margin.
40-50 years ago when you could get Springfields, Mausers, Enfields, and Krags for a dime a dozen, nobody gave second thought into cutting them up. You could get a darned nice hunting or target rifle for less than a comparable Remchester. Fast-forward to the present, and it's a different story in both availability and cost of conversion. Granted, it's your gun and your Dremel tool, so it's entirely one's prerogative to "modify" such pieces as they see fit. It goes back to the old, "It's your soap and washcloth, you can wash as hard and fast as you want to" analogy.