It’s important to know how much of foods ‘X, Y, & Z’ you should eat today.
Of course, that will change daily.
After you’ve been on your individual (redundancy intended for emphasis) for a while, you begin to put together different skills you have acquired.
One of those skills is the ability to weigh & measure without using a food scale – with a very high degree of accuracy.
Combine that with a clear intuition of what your physical body is feeling, and an awareness of your typical baselines, and you won’t need a food scale.
This assumes, of course, that you’ve invested time experimenting with weighing & measuring and actually recording what works, and what does not.
If you haven’t invested time into that experiment, then you may need to.