While I could certainly agree with that. Even if that dude could not get weapons legally, if he was really intent on killing a bunch of people, he could have bought them from the gang bangers on the street.
This lawsuit will probably not go anywhere. The shooter didn't have to get the guns from “gang bangers”. He only would have had to purchase them from legally from a private party. There are no restrictions on sales of firearms between private parties in Texas and there is no background check required in this type of transaction.
“This is the most common transaction and by far the most profitable one to boot. In the state of Texas you do not have to transfer ownership of the firearm via a dealer, nor do you have to have the firearm re-registered as there is no such firearms registration in the state of Texas.”