These WiFi settings pages had not changed since the time of Windows Phone 8.1. The new look is Windows 10 one and already present on Windows 10 PC version. So, Microsoft seeks to unify it even more.
Check the screenshots above to check how it looks like now. Microsoft has last pushed Windows 10 Mobile Build 14915 to Insiders in Fast Ring and after a pause last week, this week may bring newer builds. Till now there have been no significant changes or new features but Microsoft may be just starting to do so.