The last season with only one top-flight league title among the managers was 1947-48 (George Kay of Liverpool in 1946-47). I guess mainly due to the seven-year gap due to World War II meaning high turnover.
@orbinho.bsky.social Had a stats question, so joined bluesky to ask you! When was the last time a Premier League/First Division season started with all the managers combined having only won 1 PL/FD title between them? Surely not for a long, long time, right?! Has it ever been less?