Microbes use many of the same minerals and other things to build their biofilms, so if there’s enough competition, candida is going to get closed out. Beneficial bacteria also create various by-products that destroy candida (and other pathogens) and make it hard for it to grow. If your immune system is functioning well, it’ll be attacked in other ways if it starts to grow too. I don’t see any reason you’d need to rely on supplements for the rest of your life if you can attain good gut/digestive health and get the candida under control.
Of course, if you go back to a Western diet that favours yeasts and pathogens and simplifies gut flora, you’ll always be at risk of dysbiosis, just like most other people. It won’t necessarily involve candida, but gut flora imbalance seems to endemic. It’s linked to everything from obesity and diabetes to arthritis and MS, so it’s likely you know more than one person who could benefit from what you’re doing too!