I suggest 96 people getting SUCCOTASH in the 7 by many is a fair display of how common, or uncommon that word is in the English speaking world.
Not necessarily. Only 69 people found
toccata in this same puzzle, and yet no one is complaining about it, neither at present nor in the past seventeen years.
This is not to defend
succotash. I know it well, having eaten it quite a bit as a child and having heard Yosemite Sam exclaim it for far too many years; however, it was the last or next to last word I found. The combination of letters was difficult for me to assemble from the mix.
The better reason to adjust its status as a common word would be that its use is almost exclusively North American, so far as I am aware.