It's incorrect to be in the delusion that you have to move to the valley to be a top company, but that depends on the definition of top, which here is valuation and it's hard to beat valuations that the Silicon Valley can afford and help realise because of the ecosystem that's formed over the years.
YC is based in the USA, so it's not really a surprise that you'd have to move there to be a top YC company.
You can build a top company anywhere in the world, even if your definition is that of valuation, the process remains by and large the same that YC advocates in documents such as the startup playbook and the startup school courses (the parlance may be different in material from different sources), and I believe that it gets easier to build a top company where you are if you make your own definition of top as valuations could be deceiving.
You don't necessarily have to move to SV to make a top company by valuation, top YC company: stats suggest yes, but I still believe there's slim chances you could do it from anywhere, YC tries hard to be inclusive, however their location presents them with constraints, hence the stats.
To decide where to move in order to build a top company, first understand what is your definition of a top company and whether you really want to disrupt your life, move to the valley, and build what the world calls a top company.
PS - No disrespect to valuations, the Silicon Valley or anyone's ideologies.