I would like to understand why you are reluctant to take investment. As I see it, there are two possible paths:
1) You take investment from YC, you become part of the community, you get advice, but your desire to remain King is respected. It seems to me that if this were the outcome, moving to the Bay Area for three months and incorporating in the US is a fair exchange.
2) You take investment from YC, you become part of the community, you get advice, AND there is now a perceptible push to make Tarsnap more like a "make-me-Rich" company rather than "keep-me-King" company: they keep on suggesting that you raise more money and start doing things that would increase the valuation of the company but that you would fundamentally disagree with, etc. etc. Certainly this would not seem like a fair exchange.
IOW, what I am trying to ask you is this: is the fundamental reason why you are reluctant to apply to YC Core is that you are concerned that your desire to remain King will be challenged? Or is it something else entirely that I am not seeing? Because certainly incorporating in the US is a schlep, and finding housing in the Bay Area is a schlep, but I can't imagine those being the fundamental reasons for not applying to YC considering the benefits of the community, and getting a bunch of money from YC, if it comes with no strings attached (aside from the moving and incorporation mentioned above), can't be a bad thing, even if you don't need it.
No one in their right mind would argue that Canada can't produce a company that has global reach, but that consists of a founder that lives in Canada, and a UI programmer that lives in Romania. It doesn't seem to me that those are the examples that Canada is lacking.
It seems perfectly reasonable, however, to argue that Canada doesn't have the investment ecosystem that is capable of creating a <insert your favorite company whose founders chose rich rather than King> on the same scale as the Bay Area - but it doesn't seem like that's the example you are trying to set anyway.
Edit: remove Spotify example, as it's Swedish.
But I don't think YC makes many mistakes, so I'm inclined to conclude that the third of those possible purposes is not why YC set up the Fellowship program.