Jonathon sits next to 4 phonetic neighbors — Jonathan, Nathan, and Nathaniel are the closest matches by sound. Most share Jonathon's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"God has given, gift of God"
"modern invented name, possibly dark one"
"fortress, walled Roman camp"
"courage, bravery"
"salvation of the Lord (via Isaiah element)"
"my Lord"
"people's champion"
"sun, lord"
"cross, crossroads"
"descendant of the black-haired one"
"forest guardian, one who patrols"
"Chinese unicorn, bringer of good fortune"
"of the lyre, lyric poetry"
"spear, marksman"
"my messenger, my angel"
"God has made"
"elder, one of authority"
"stubborn one"
"God will hear"
"dreamy obscurity"
"bright pledge, noble hostage"
Similar sound: These names share phonetic patterns with Jonathon — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Hebrew (Yonatan: YHWH + natan) origins, giving them the same cultural heritage as Jonathon.
Rhythm: Jonathon is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.