Only use right now is for generating character and map art. It's hard to think of much use other than art for AI in TTRPGs. Even if you want something advanced and computerised that can do the math for you, all you need is simple scripting for that, not AI, since FoundryVTT can automate all of that already with JavaScript. You can use AI to help with writing and ideas if you're DMing, but besides that taking the fun out of it, you will have better results and more importantly improve your own skills by doing it yourself. Doing it yourself is even more important since probably more and more people will rely on AI to do those things for them with time, meaning there will be a lot of people with zero skills, creativity, and no dedication.
In the future there'll no doubt be AI DMs, but even if they get very good, unless you're an autist, they'll be a poor substitute for the social experience of playing TTRPGs with friends (short of strong AI and buying sentient robot D&D TTRPG slaves you can keep in your basement). Future of AI in RPGs is more important for video games, not TTRPGs.