After spending the last year becoming technical (data science -> software eng) and seeing all those "I learned to program in 3 months and got a job at Google" videos, I'm convinced that this is just the dunning kruger effect of not knowing enough about the subject to understand how long it takes to become competent.
Furthermore the "I learned x in y time" meme is almost always perpetuated by false beginners. I remember seeing an "I learned Italian in one week" video where the guy actually knew some Italian beforehand. He also had previously learned fluent French and Spanish beforehand, so to say he learned Italian from scratch is a huge stretch.
Most people don't learn languages at the FSI so to expect it will take you as long is not accurate. It may take you way longer, or maybe you'll be way faster depending on how good you are at learning languages and how much time you're putting in each day.
But yeah, to summarize, the FSI rankings are good, but I don't agree with the actual estimates.