I'm using the LG V20 and am able to sync my 80+ playlists (and 20k+ tracks) with no issues. Using wired or WiFi. You say you're using MTP. Are you ticking the box that says something like "Allow MTP syncing"? If so, you're using a very old version of MB as that dialog has been removed and is no longer necessary.
So, what version of MB are you using? (help > about)
What format are the playlists?
How are you syncing?
A screenshot of your sync settings might be helpful, along with one of your selected music