Bryan sits next to 5 phonetic neighbors — Brian, Ryan, and Byron are the closest matches by sound. Most share Bryan's Irish-rooted cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"sorrowful (folk etymology via French)"
"young dog, whelp"
"Roman pilgrim"
"holy, sacred one"
"son of David"
"river, great river"
"always king"
"battle (possible Irish Gaelic root)"
"divine messenger"
"son, young boy"
"man of prayer"
"defender of men"
"defender, protector"
"from the bridges"
"son of Madoc"
"steadfast defender"
"firebrand"
Similar sound: These names share phonetic patterns with Bryan — similar vowel sounds, consonant clusters, or rhythm.
Rhythm: Bryan is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.