Doesn’t alcohol metabolize at an average of about one drink (12 oz 5% beer/1.5 oz 80-proof alcohol) an hour? And faster for habituated drinkers?
As both a drinker and a runner I can give anecdotal input that yes, you will be able to push yourself harder and run faster if you give up the booze. That said, if you are a 40+ year old, you are already doing pretty good and may not be able to push it much farther. If you are younger and generally in shape, then certainly you could see improvement.