When you share a Zip file in Google Drive, you land on a page to view all the files inside the zip file and to download the entire file the user has to click File → Download. I've noticed a lot of users don't get this so I actually have to tell them to click File → Download when all I really want to do is give them a link to directly download the file.
For the moment, you have to build the URL manually.
YourIndividualID is the ID of the respective document (zip file). You get it either from the URL or by clicking File → Share and copying it from the sharing URL.
Also, while viewing the content of zip file, you can click Ctrl+S to download the whole directory as zip file.
Replace "YOUR_FILE_ID" for the ID of your file
This is also a good link:
with antivirus inactive, and you can download files of any size.
Just replace the xxxxx by the file ID that you get when sharing a file:
I wrote a user script for this you can install with Tampermonkey/Greasemonkey: https://greasyfork.org/en/scripts/10052-google-drive-direct-links