You can go but you shouldn’t go. You might be fined. You might not be left back in but you definitely will. You need a test, even if you’re vaccinated. There’s variants already here but you can’t go unless you bring one in.
I think they avoid US flights. At the end of the day you can’t get in if you aren’t a citizen or have a specific visa and if you come back, you have to be vaccinated or you’re put in detention. I had asked you before and asked another couple of people and they never saw the Guards. One said he encountered them but US passport and you’re waved on.
If you really want to travel abroad, not hard to come up with a reason. Just say you’re emigrating and give them some booking in Spanish they won’t understand. I’ve heard of people going to the U.K. with fake interview emails.
I contacted a commercial real estate agent over, set up appointments for viewings of properties, printed documents. Was never asked but alibi was ready if needed.