Beside lapping the field offensively, he was a Hall of Fame level pitcher who held the record for consecutive scoreless innings in the World Series for longer than he held the record for home runs in a season.
I'll bite here - Babe Ruth was not a Hall of Fame-level pitcher.
Ruth was a good pitcher - well above average, in his time on the mound. He was arguably the best pitcher in the American League in 1916, leading the league in ERA (and ERA adjusted for ballpark) and finishing a narrow third in innings pitched. He was playing in front of very good defense, and Walter Johnson, who pitched 46 more innings at nearly the same level of effectiveness, was almost certainly more valuable, but finishing second in the league to Walter Johnson is hardly a problem. However, that's basically it for Ruth's career as a dominant pitcher. He was a good pitcher in 1915, and a good pitcher in 1917.
He was a good strikeout pitcher in 1915 and 1916, but his strikeout rate took a tumble in 1917 and was barely above average. It took another tumble in 1918 - maybe because he was distracted playing the outfield, and had he remained on the mound it wouldn't have dropped as far, but it seems that he was losing his ability to strike batters out and was near the bottom of the league in strikeout rate. It continued to fall in 1919.
Maybe, with dedication to improving his craft, Ruth would have remained a good pitcher for some years, but losing your strikeout rate to that degree and at that age is a gigantic red flag for me. My best guess is that, if Ruth had not been much of a hitter, he would have been out of baseball by 30. That would not have been unusual in that era for pitchers (it still isn't, really).
Babe Ruth, as a pitcher, has more in common with Bob Tewksbury than Tom Glavine. Ruth was better, but the same principle applies - pitchers who don't strike out batters don't last long, with very few exceptions.
Babe Ruth was a great hitter - a tremendous, transformational hitter - who was also a good pitcher for a few years. He wasn't a Hall of Fame-quality pitcher
and a Hall of Fame-quality hitter.
He does all of this and still has a career batting average of .342. Still steals 123 bases in his career (finished top 10 in the AL twice) and hit 136 triples more than half that none other than Rickey Henderson hit in his career. He also would have been a Hall of Famer as a pitcher in which he won 94 games had he stuck with it. He has this image of trotting around the bases after a home run on grainy footage and I think people figure that is all they need to know, but there was so much more.
I'll add to this that Ruth was not a good basestealer - he was caught almost as often as he successfully stole (even in that era, that was below average) and his triples reflect the parks he played in, not his actual speed (which was good when he was young - he was capable of playing center field - but never exceptional).
Even in his most successful season as a basestealer (1921, where he went 17/30), Ruth was barely above league average in success rate, at 56.6% compared to a league average of 55.6%. Ruth was not generating a lot of runs on the basepaths (his most famous moment as a baserunner was being caught stealing to end the 1926 World Series with Bob Meusel at the plate and Lou Gehrig on deck).
