If this was based a telephone poll, I think that the percent polled who would tell an anonymous caller that they own a firearm might be a little higher the percent who would tell an anonymous caller their SS number, credit card numbers and passwords, but it's nowhere near 100%.
Based on the number of NICS FBI background checks since 1998 (269,485,959 through August 2017) and added to estimates of the minimum number owned before the NICS system was initiated, there must be at least 400,000,000 firearms in the United States.
So my estimate is that about 97.2% of Utah households own at last one firearm.
The article doesn’t cite methodology and only refers to City-Data as the source.
City-Data actually lists 101 counties and states that none of them are in the states with the strictest gun control laws.
However, if one lived in one of those states would one acknowledge their ownership?
I think polls like this are indicative rather than accurate and are in large part for entertainment.