Seriously? We don't look particularly attractive to other countries right now.
They only let us into Spain, Greece and Malta because we're so important to their summer holiday trade.
Unless Bulgaria is way up there with vaccinations, we present a serious risk to the health of their residents right now. We're basically like India was to us a few months ago. So they've very sensibly closed the door on us. I'm sure there's plenty of other Europeans who'll fill their tourist beds.