Above example is not a test of your programming skills. May be you are great NodeJS ninja who doesn't need to care about any of this. I think there is two types of hiring that often happens (1) for a specific project, specific task (2) long term member of the mission that company has.

For #2, I prefer to hire people who are generalist problem solvers. They need very strong coding skills but more than that they need to be able to operate in new domains easily and adapt. If I was running a startup, I would need them to work on MySQL database one day and react-native stuff other day and perhaps also pick up some of deep learning practitioner skills two months down the line. Above example question doesn't expect candidate to be familiar with floating point representation but it is interesting to see what they might have thought if they were the ones doing it. Assuming everyone works with numbers all the time, people are hopefully familiar with basic issues of precision, rounding etc.

There's not one kind of programmer. You may not be good at algorithms, theory of computation or numeracy. There are huge swaths of important work that don't include these attributes. But there are also many that do. And for those, you may be unqualified as this is not a particularly challenging or deep question for this branch of our field.