Okay. Let’s try that again.
Had to take a moment to unravel my thoughts.
Hopefully I’ll make more sense the second time around.
Logically, it looks like “one” is the noun and so the verb should be “is”.
But that seems to go against the rule of thumb about stripping things down
to find the main noun/person/place/thing that is doing the verb/action.
Example 1: “One of the ten people is…”
“One” is the noun because “of the ten people”
is easily omitted or replaced while keeping the same meaning.
“One is…”
“One of them is…”
“One of the brothers is…”
Example 2: “People” is the noun because “one of ten”
is easily omitted or replaced while retaining the same meaning
“People are…”
“Some people are…”
“Ten percent of people are…”
Example 3: If “One of ten people is…” were correct,
“of ten people” should be easily omitted or replaced while retaining the same meaning.
“One of ten people prefers Brand X.”
“One prefers Brand X.”
If you are speaking of percentages, the second statement is not true.
The second statement is only true if you are speaking of a particular group of 10 people.