I know to wait is common, but doesn't waiting work here in some cases?
ex)It is a frustrating experience (waiting/to wait) in a crowded emergency room when you need treatment.
'Waiting' is more common in my dialect (AusE). This would apply to most constructions of this type:
"It's [a] frustrating [experience] having to wait. (Having to wait is frustrating)"
"It's hard studying for exams. (Studying for exams is hard)"
"It's [a] sad [experience] seeing people starving on TV. (Seeing people starving on TV is sad)"
"It's fun playing in the surf at the beach."
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