The last time I looked deeply into setting up notifications in Google Sheets, the options were either unclear or required creating custom scripts. Now, granted, this may have been over 5 years ago. I developed other habits and routines in order to keep track of various collaborative sheets, including setting up those sheets as Startup tabs for my browser so I had a constant reminder to check on them.
A question came up last week that prompted me to look into it again and sure enough, Google has introduced a version of notifications that is user-subscription based. That means an individual has to opt in (the document owner can't force notifications on participants). If it's with a small enough group, though, it's not too much of an ask to request that folks enable notifications especially when one of the options is a daily digest.