Then why do some people eat ultraprocessed foods frequently and remain slim, while others don't? Because those others eat too much, right?
Because they have a different microbiome. Study the Zoe research. And/Or they do more exercise.
You have to deal with the why of people eat too much before you deal with the what, and it isn't just down to foods being over processed and moreish. Because some people can eat those foods and remain at a healthy weight, and others cannot. The why is paramount. If it continues to be ignored then the obesity crisis is only going to get worse and worse.
You've ignored most of what I've posted which was about the food industry setting a level of portions.
As a nutritionist you will know that most people put on weight slowly by increasing their calories gradually, over time. Don't they say that eating a couple of (extra) biscuits everyday for a year (and not increasing calorie expenditure) can result in a stone weight gain in a year?
I wonder who your clients are? Are you promoting yourself as weight loss nutritionist? If you are and your clients can afford your services, you're getting a self-selecting bias if you website says 'I can help you lose weight - are you a yo-yo dieter?'
Most dieticians I know through my work (some very good ones who have won national awards like Marianne Williams) are seeing clients (as a PP said) who want help with IBS/FODMAP, or allergies.
There are plenty of weight loss coaches out there who aren't nutritionists but who work with clients on their weight. The client usually knows what they are doing wrongly and the qualified coach can help them.
If emotional-eating is your USP that's fine, but it's not the only reason people are overweight.