It maintained the "cards" layout that had recently been introduced, which categorized videos into clean, white blocks, a precursor to the modern Material Design.
This is the hidden killer feature. Modern YouTube requires Google Play Services (GPS) for login, ads, and analytics. GPS is notorious for draining battery and phoning home every few seconds. youtube version 5.9.0.13
about why old layouts were better, would you like me to find community-made patches or "revival" projects? YouTube 5.9.0.13 (arm) (nodpi) (Android 4.0.3+) - APKMirror 2 Oct 2014 — It maintained the "cards" layout that had recently