Brett sits next to 4 phonetic neighbors — Bret, Brad, and Trent are the closest matches by sound. Most share Brett's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"a Breton, person from Brittany"
"short form of Asher (happy, blessed)"
"who is like God"
"treasurer, keeper of treasure"
"grace, beauty, ornament"
"reborn, born again"
"from the isle"
"emperor, ruler"
"descendant of Braonán, tearful one"
"son of Bron"
"of the angel, son of Angelo"
"son of the south"
"resolute, crafty"
"battle, warrior"
"charming, wily"
"claw of a bird of prey"
"from Dayton"
"land desiccated from water"
"acquired, possessed"
"diminutive of Scott"
"bold and modern (cultural meaning)"
Similar sound: These names share phonetic patterns with Brett — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Celtic/Old French origins, giving them the same cultural heritage as Brett.
Rhythm: Brett is a 1-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.