And unless you have absolute proof that they are using third party tools, nothing will happen. Most of these mods would require the player to outright declare in game that they are using them. Streamers can show parsers and other mods without worry of a ban, and that GM response is a pretty standard GM response. The game doesn't need any additional protection than it already does; it increases the chances of additional issues from the large variety of hardware setups or the variety of other software people have on their computer (like which Anti-Virus they use). For example, Capcom tried adding all sorts of protection to Monster Hunter World throughout its lifetime and none of them really worked and all they did was cause issues for people who did not use mods. Those protections added so much extra overhead that the game ran worse and could often trigger people's Anti-Viruses.
If anything, you are more likely to get banned if you go up to someone ledge sitting and begin yelling at them for "possibly" using third party tools. The point of the no third party tools rule is not to witch hunt people using them, it is to stop people from using them as an excuse to harass other people. That's why if someone is harassing another person for their parses, they would get charged with harassment first and foremost, rather than third party tools usage. So even if they are able to say something like, I was joking about using third party tools, they can still be banned for harassment, which would be the primary charge, because that is the most important one.
Fact is, things like ACT and GShade are here to stay. They have been a part of the game's culture since ARR, always have been and always will be. Any attempts to try to curb their usage further than what has been done will do far more harm than good. You dramatically increase the chance of technical issues all for the sake of what is essentially witch hunts. The game would see no benefits from these witch hunts.