I just backed up using new LR on Win 10....no problem that I know of. I must admit that I don't sit around for it to complete, as it takes a while. I actually like the old not zipped version as it took less time. I would later use an automated plugin the next time LR opened to zip the backup in to background.
On my machine, LR's backup of the catalog takes about a minute, including checking catalog integrity, compressing the backup and optimising the catalog. Within that, compressing the backup is less than 15 seconds.
I just tried compressing the catalog with Windows Explorer built-in compression (probably not the fastest compression around!) and it takes over a minute, but compresses the catalog to a smaller size than LR managed (about 60% of the size).