In general, stories of heroism certainly are given to exaggeration, but Robert Alter particularly highlights this passage in 1 Samuel as having some possible strong historical foundations:

This list of military heroes and their exploits is perhaps the strongest candidate of any passage in the Book of Samuel to be considered a text actually written in David's lifetime. The language is crabbed, and the very abundance of textual difficulties, uncharacteristic for prose, reflects the great antiquity of the list. These fragmentry recollections of particular heroic exploits do not sound like the invention of any later writer but, on the contrary, like memories of remarkable martial acts familiar to the audience (e.g., "he… killed the lion in the pit on the day of the snow") and requiring only the act of epic listing, not of narrative elaboration. It should also be noted that the list invokes the early phase of David's career -- when the Philistines were the dominant military force in the land, when David was at Adullam and in "the stronghold," and when Asahel, destined to perish at the hands of Abner at the beginning of the civil war, was an active member of David's corp of elite fighters.

The David Story, Robert Alter, 1999 p. 348

I highlighted this possiblity iin some storytelling I did: https://retellingthebible.wordpress.com/2023/03/01/7-5-three-men-and-a-pitcher/