"a huge disappointment" is correct and usable in written English. You can use it to describe a situation or event whose outcome was much worse than expected. For example: "I was expecting to get a promotion, but I got passed over for the position; it was a huge disappointment.".
David: A huge disappointment.
This is a huge disappointment".
It's just a huge disappointment".
That was a huge disappointment.
"It's a huge disappointment to get bronze.
He's a huge disappointment to me".
"He's been a huge disappointment," she said.
Ludwig does not simply clarify my doubts with English writing, it enlightens my writing with new possibilities
Simone Ivan Conte
Software Engineer at Adobe, UK