Notable facts:
1) shooting took place in a state with fairly strict gun laws
2) this guy was on law enforcement radar for threats to commit a mass shooting at his school
Noteworthy because both gun restrictions and increasing police are often suggested as simple solutions to the problem of stochastic terror, but there's really very little reason to believe either would be effective.
Maybe total prohibition of guns, including a mass confiscation, is something that might do some real good, but that's so politically non-viable it's not really worth mentioning. Little bites of gun control, like banning certain features and calibers on a state by state (or city by city) level, seems unlikely to do much good.
Police are an inherently reactive force. Even with all the money in the world, there's little they can do to prevent crime. Even if given expansive powers that would require further erosion of civil rights in the name of taking more proactive action against would-be shooters, police routinely show themselves to have massive blind spots for right wing violence. Hell, I imagine a significant portion of US cops more or less believe the major elements of this "Great Replacement" theory that motivated the attack.
Each attack only serves to normalize violence as a legitimate means for achieving far-right political goals and emboldens others to take similar action.