@b6hydra I dont. Even on cave dives where the space is pretty tight I am still pretty comfortable. I am sure some people do, but those people probably wouldnt SCUBA dive in the first place.
That said I will say this, BEFORE I learned to SCUBA I would feel something you might call agoraphobia when I was swimming in the middle of the ocean with no visible bottom. Though Diving in areas like that quickly cured me of those feelings.
Not related to agoraphobia or claustraphobia I can say your first few dives can be scary, my first 10 were. But the fear is more like "If my equipment breaks and my dive buddy doesnt see me I might die". Thats a healthy fear though and ultimately is what lead me to go tech because in tech you have a backup for everything, even tanks.