Valve announced a replacement feature for both Family Sharing and Family View. Currently in beta.
Features:
- up to 5 members
- game sharing
- parental controls
- allow access to appropriate games
- restrict access to the Steam Store, Community or Friends Chat
- set playtime limits (hourly/daily)
- view playtime reports
- approve or deny requests from child accounts for additional playtime or feature access (temporary or permanent)
- recover a child’s account if they lost their password
- child purchase requests
You can mark games as Private in your library now. It hides your ownership, play stats, etc. It doesn’t specifically say it disabled Family Sharing but it’d be silly to keep that. There is also a Hidden Games section which stops it from showing up on your list.
https://help.steampowered.com/en/faqs/view/1150-C06F-4D62-4966