Good morning @aguy and welcome to Mayo Clinic Connect. I see that you have recently joined Connect. It's very jarring to expect to breathe easily and find that they can't. Firstly, you aren't in any danger if your lung tests show that your lungs are working properly, at least from your SOB. Shortness of breath—in some very large paraesophageal hernias, the stomach may push on the diaphragm or compress the lungs contributing to a sensation of shortness of breath. There are many other reasons for shortness of breath in addition to a paraesophageal hernia.

Swelling from surgery can last more than a year and cause secondary problems. There might be another cause. Please read this post:
https://connect.mayoclinic.org/discussion/mysterious-shortness-of-breath/?pg=132#comment-203387
Quite a few people in this group complained about this during the first, very scary times of COVID-19. Who wouldn't have been?

Please remember that I am not a medical professional and can only make suggestions, from my own education and experiences.

Does this all make sense to you?