I haven't seen a Windows upgrade (note: UPGRADE) destroy data in a meaningful way in.....I don't even know how long.
As someone who has worked closely with NTFS, I can tell you that it's not far fetched to think that someone's NTFS partition could have been corrupted. There are no backups of the file index (unless they changed it since Win7), so if your file was fragmented and the index is lost then any file that is fragmented will be unrecoverable with the publically available automated tools. However, I can also tell you that losing the filenames and directory structure of all your data can be just as devastating as losing the files themselves.
That's a neat trick, unless they mean their IDEA of their computer rather than the physical hardware. Windows is shitty, not malicious.
If this were 20 years ago, you would be 100% right. Unfortunately, UEFI has made it entirely possible for a ill-tested operating system installer to brick your system.