In a game this makes sense, cheaters ruin the competitive aspect of the gameplay. But here people are objecting because there's no competition. VRChat's claims

In a game this makes sense, cheaters ruin the competitive aspect of the gameplay. But here people are objecting because there's no competition. VRChat's claims are that modded clients result in security exploits for unsuspecting users and can cause instability for non-modded users. So the question arises, can VRChat plug these problems without resorting to anti-cheat? Was anti-cheat just the lazy option, or are there inherent aspects of the client which make it hard to plug these security exploits or the instability?