There are often storm shelters in areas hit by weather like this, and there was ample warning about this storm system, so at least some of those that don't feel safe in their homes could have sheltered somewhere else if they were free to do so.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
To repeat, a tornado is on the ground. TAKE COVER NOW! Move to a basement or an interior room on the lowest floor of a sturdy building. Avoid windows. If you are outdoors, in a mobile home, or in a vehicle, move to the closest substantial shelter and protect yourself from flying debris.
https://mesonet.agron.iastate.edu/vtec/#2021-O-NEW-KLSX-TO-W...
If you are in a reasonable building (such as a typical home) when a tornado warning is issued, do not seek alternative shelter. Seek the most secure area of the building you are already in.
You can search all the warnings/watches here: https://mesonet.agron.iastate.edu/vtec/search.php#byugc/MOC1...
I will note that the watch (which proceeded the warning) suggested to precautionary action.
https://mesonet.agron.iastate.edu/vtec/#2021-O-NEW-KLSX-TO-A...