Yeah but smaller startups might be more open to non-US applicants, FAANG and other more established companies don't seem to be interested in hiring abroad.
That's what makes the early startup scene the only thing available for some.
How come? Most large companies have big legal/HR departments that are very efficient at the whole visa application process. A small company won't have that expertise/staff. I mostly see startups being more concerned about the visa status of applicants.
Remote + non-US is not as welcoming, so the hurdles are way higher as it's not fitting the usual way. While startups have no prior experience anyway, so it's easier to convince 1-2 people instead of changing a whole system (I believe).
That's what makes the early startup scene the only thing available for some.