You are implying that only competitive sport swimmers can actually swim.
It's certainly possible for a autodidact swimmer with such a background to go to the Y pool and start doing laps until they figure out out on their own, but that's pretty uncommon. And it's also possible for somebody to pay for enough private lessons to become a competent swimmer, but that's also fairly uncommon. In my experience every licensed lifeguard I've ever met was currently or formerly a competitive swimmer; that's not a requirement but realistically only competitive swimmers could accomplish the 300 yard perquisite swim required to qualify you to receive training. (As for selection bias, in my training course there were several without competitive swimming backgrounds who tried, but failed.)
(In some outlying situations, perhaps such as a coastal community where surfing is common, the above might not necessarily be true. But for your typical community I'd say it's a good bet that anybody who hasn't swam competitively will, if they're able to swim at all, have poor form and fatigue quickly.)
Maybe there are more pools here.
I used to swim 1k couple of times a week (no breaks) just to "keep fit" not even competitive. I considered that normal.
That same pool is also where private swimming lessons for all ages were available for a modest fee (that program was subsidized by the pool's existence but otherwise self-funding. I worked as an instructor in that program for a few years and got a modest paycheck for it.) That pool was also use for practice and meets for the swim club (competitive swimming for young children) and the swim team (competitive swimming for teenagers.) Private lessons were mostly attended by young children, their parents stopped paying for it once they were reasonably confident their child wouldn't drown and it was very rare for anybody as old as a teenager to take those lessons. The pool was also open to the public once or twice a week for a dollar or two and there was a lane set aside for lap swimming, but it was rarely used.
I'm not sure what the bottleneck was that prevented more school-hour swimming lessons during their scheduled gym classes. It may have been the busing requirement, since there were a handful of elementary schools in the district that were not close to the school building that had the pool.
I have always been a pretty poor swimmer by local standards. But that is not because others did any more lessons in school than I did (those lessons were quite limited).
Some might have had more private lessons than me; but I think the main difference is that they bedded down what they had learned in lessons doing recreational swimming. Which I is common in Australia, but rare where my family comes from.
Case in point: go to a public swimming pool (YMCA, etc.) when old people are swimming laps. You'll see people who are clearly not athletic swim for many tens of minutes without taking a break.
But outside those who swam on a team for more than a year (I was a competitive swimmers for more than a decade), and of course lifeguarded through my high school years, I’ve found it very rare for people who have less than a few hundred hours experience in a pool (in a non-play way) to understand their safety limits.
My adult swimming standards are going to be 1. Can you swim 1 mile open water 2. Do you know what to do in a rip tide