I think you've missed the point there. If I use moderate exercise to get my maintenance calories, I can eat over 2000 calories -500 for weight loss gives me 1500 calories however I've overestimated my activity level and have a Sedentary job with no exercise that raises my heart rate and 1500 calories is actually my maintenance allowance so I'm not going to lose any weight because even though I think I'm in a 500 calorie deficit, I'm actualy not, I'm just eating what I need.
It’s not that I’ve missed the point, I don’t think I understand the point you’re making?
You said steps don’t matter if you’re on sedentary calories? I said no one should be on sedentary calories. Even if you have an office/desk job you shouldn’t use ‘sedentary’ when calculating TDEE, you would still be lightly active seeing as you get up to walk to your desk job, you’d go up and down the stairs during the day, you’d go to the kitchen to make food, you’d maybe walk the dog for 20 mins etc.
I think perhaps you have misunderstood the activity levels, exercise that raises your heart rate (PAL) makes a very small difference to your daily calorie expenditure unless you’re training for hours a day, it’s much more important to focus on NEAT which includes walking, this is why using steps to calculate your TDEE is really useful.
The example you’ve given is just an example of calculating TDEE incorrectly, if that’s genuinely the case and someone who is lightly active has calculated their TDEE using ‘moderately active’ then yes, of course they may not truly be in a deficit. Same as people who say they are ‘lightly active’ but actually they walk 10k steps a day and do zumba a couple of times a week, they should be ‘moderately active’ so can actually eat more than they are, making their weight loss journey more enjoyable and sustainable.
Ultimately for me, the point is that walking daily is beneficial to everybody, regardless of your maintenance calories or not, it will contribute to overall better health and wellbeing & can play a big part in weight loss by increasing your NEAT