Yes bro — that’s mostly true.
In the U.S., people usually make fast, broad, surface-level ethnic/racial guesses. They don’t dig deep into ancestry like Europeans often do. Here’s how it works:

1. Americans think in very broad categories
Common categories Americans use:
White
Black
Hispanic / Latino
Asian
Middle Eastern
Native American
Mixed
These are huge umbrella groups. Someone could be Greek, Serbian, Irish, Kurdish, Armenian, or Slovene — and many Americans will just say “white.”
South Asians from different regions? Usually just “Indian-looking.”
Middle Easterners from different ethnicities? Usually just “Arab-looking.”

2. Americans rarely ask about detailed ancestry
Most Americans:
Don’t know their own ancestry very well (except “Irish,” “Italian,” etc.)
Don’t care about fine distinctions like Balkan, Visigothic, Anatolian, etc.
Use visual impression rather than genealogy.
In Europe someone might ask:
“Are you Serbian, Roma, or Albanian?”
In the U.S. they ask:
“Where are you from originally?” or “What are you?”

3. Visual cues matter the most
Americans focus mainly on:
Skin tone
Hair style
Features
Clothing (tracksuit vs. suit can also influence assumptions!)
Accent
You experienced this yourself when asking how you’d be seen in the U.S. — they wouldn’t guess “Roma,” “Vlach,” or “Banat-Serb.” They’d go for something like:
Mediterranean / Latino
Middle Eastern
South European
Sometimes even Mixed
But not detailed.

4. Americans don’t distinguish between many groups Europeans see as different
Examples:
Greeks, Italians, Croats, Serbs — all “white” or “Mediterranean.”
Pakistanis, Indians, Sri Lankans — all “South Asian.”
Lebanese, Turks, Iranians — often seen as “Middle Eastern,” even when not accurate.

5. Many Americans assume background based on vibe
Clothing style, beard, haircut, tattoos, and attitude strongly influence assumptions.
A guy in a Puma tracksuit, strong build, darker features — many Americans might guess:
“Latino”
“Mixed”
“Mediterranean”
“Some kind of ethnic European”
Even if they’re totally wrong.
If you want bro, I can also explain exactly how YOU would be categorized in the U.S., based on your latest photos.