What will happen if professional sports are canceled, and coaches and athletes are sent to factories? Stupidity and savagery, that's what will happen. The meaning of professional sports is exactly the same as the meaning of any profession that exists in our time. Every craft, every business began with amateurs and enthusiasts. And about factories. I don't know who you are by profession, but if you are not a turner, a locksmith or a seamstress-minder, tell me, would you be interested in working at a factory? What would be your motivation? Would you feel like doing what you love?
Professional sports are a child of developed capitalism. As well as professional art (music, cinema, literature) and media.
200 years ago, 80-90% of the labor force was employed in agriculture, 5-15% in the production of non-food products.
100 years ago 30% were employed in agriculture, 50% in industry. People began to appear who were free from labor for the sake of survival.
Now in developed countries, 1-2% work in the agricultural sector, and 10-20% in industry. All the rest is service.
The meaning of professional sports and other entertainment is to decorate the gray life of a modern person who works a maximum of 9-10 hours (+ lunch break and travel) only 5 days a week.
On the other hand, professional sports and entertainment provide jobs for those who would otherwise be unemployed.
If athletes are sent to factories, what will they do there? The market for goods is already saturated. In addition, you will have to build a bunch of factories to accommodate athletes and artists.
Still, being an athlete is better than a parasite or a criminal.