They don't mean do all those cuts each time you mow. You mow the grass in one direction one day, and then a few days later when it needs cut again, you mow a different pattern.
When I used to mow neighbor's yards as a kid, I'd do a crosshatch pattern that I'd rotate 45deg each week, orthagonal vs diagonal. Just doing one direction looks fine but a crosshatch looks even better, especially if they have thick, healthy grass. I wouldn't be as meticulous on the side and backyards, those would just get a single, slightly overlapping pass in whatever direction was convenient unless they had a really nice backyard, then I'd do extra there.
People like that golf course look and I'd get nice tips for doing it.
I do this very thing in the fall when all of my neighbor's trees drop their leaves which blow into my yard. I don't bag leaves. I mulch them. To get them down to a respectable looking yard, it can easily take this many passes. I do it all over again in the early spring towards the end of February when the Live Oak trees in my yard finally drop their leaves for the year. According to my watch, I can cover more than 2 miles just taking my mower for a walk on those days.
Depends where you live, what season, and what equipment.
I live in the PNW where the grass grows crazy fast in the spring, and I use a reel mower since my yard is small. It needs to be done regularly, and I'm not even a "lawn guy".
East-coast of Canada, the grass grows fairly well throughout the spring and summer but I think mowing excessively is... well, excessive. But I live in a neighbourhood of predominantly seniors who wash their car and mow their lawn every fucking day, presumably because they have nothing better to do, so anytime I try to sit outside and enjoy the lovely summer days it's ruined by all the lawnmowers. Wouldn't be so bad if they used reel mowers, but of course they're all on oversized lawn tractors to mow relatively small lawns.
But then, I also like my lawn to look just a bit "shaggy" instead of clean-cut all the time, so it's possible I'm in a bit of a minority here.
The problem with a reel mower is that if you let the grass get too long the reel mower won't cut it, so you pretty much have to do it every few days when it's growing fast.
They don't mean do all those cuts each time you mow. You mow the grass in one direction one day, and then a few days later when it needs cut again, you mow a different pattern.