There were mask mandates, school and church closures. They were even more strict about it than we are today in many places. We don't typically have mask mandates for the regular flu because it doesn't kill nearly as many people. This is an interesting video on the topic....
Yeah...that's great...
There were lots of things America did in eras past that we don't do anymore.
Also, important to point out, the Spanish flu nor any pandemic/epidemic prior to or since has ended the world. In fact, the population has exploded.
So, though events such as the Spanish flu and coronavirus are bad and we should do what we can do to mitigate, they are not anomaly events, they're naturally occurring events and something we will have to experience once every so often.
The result of 8-9 billion people living relatively close to one another.
The only way to truly prevent pandemics is to figure out a way to humanely control the population. Which obviously isn't a popular endeavor for anyone to take up. Even if it was just incentivizing not having so many kids.
Even then, say if people quit f**king like rabbits and by 2075 there were a billion or two less people in the world, probably wouldn't be enough and we'd still probably pandemic/epidemic events.
So, because we can't get rid of them, we have to make them less deadly and harmful. We'd need a total cultural shift to healthier lifestyles that would allow us to better fight off infectious diseases...and good luck with that...
You think getting people to wear a mask ruffles feathers...try taking their mountain dew and pack of smokes away...
Masks are easy...
...try to mandate a fat ass walk about a mile a day...to prevent them from being in a hospital and on a ventilator, and so we have plenty of hospital space by the time the next pandemic rolls around...