Back when I was doing high intensity interval training in college I would regularly hit ~2k calories burned a day. Few things satiate the kind of hunger that gives you like a burger
If you're actually trying to manage your weight, do not increase your physical activity. Reduce how much you eat.
Most sites say running burns around 60 Calories/km or 100 Calories/mile. The average person burns 2,000 Calories a day by existing. If you ran a 10k every day, then you'd be using 2,600 Calories a day.
The difference in effort between "existing" and "runs a 10k every day" is massive, but the difference in Calories burned is equivalent to a large fry from McDonalds. So would you rather run a 10k or just take the fries out of your order?
I mean, it's weird to encourage people not to increase their physical activity if they're trying to manage their weight.
While it's true you can't out-train a bad diet, exercising, even for just 30 minutes every other day will go a long. Running a 5k will take about half an hour depending on your fitness level and will burn a good 350 calories or so, more if you're overweight. Do that 3 times a week and that's the equivalent of a about 2 meals you've burnt off (or one really unhealthy meal). Plus getting outside and exercising is good for your mental health.
In a past life I took a bunch of physiology and advanced physiology courses at uni, as well as epidemiology/ population health focused courses and worked with a lot of people on their overall health and fitness. There are so many good reasons to make time for cardio. Ignoring calories for a minute, it has an overwhelmingly positive effect on mental health and wellbeing as well as significantly reducing disability adjusted life years, maintaining balance and strength into old age and reducing the risk and severity of falls as well as a host of cardiovascular diseases.
Heavy cardio also has a startlingly fast positive impact on the visual appearance of your body even in caloric balance, which can go a long way towards keeping you motivated with any dietary changes you may be making.
Having said all that, I find that for those who are just starting their fitness/weight loss journey cardio exercise can set off an absolute rocket of hunger that can potentially undo a lot of good work. I know for me, that hunger after a really hard run can far outweigh the calories I have just burned on that run.
For sedentary individuals just coming to the table, I had way more success in terms of both results and adherence by using programs where the cardio component kicked off with fast paced walking or hill walking for many months before trying to introduce running, swimming or other forms of higher intensity exercise. All of this backed up by a solid resistance training program.
Once you are starting to see concerete progress towards your goals with something as easy as WALKING and a few weights multiple times per week it's way easier to stay on track once the hunger kicks in after your first few runs.
And then comes the fun part where your body, built for pure energy efficiency and nothing else, will try to offset burned calories by subconciously moving less throughout the rest of the day
Physically I agree with you, but psychologically it is much easier to control what I eat when I regularly go to the gym because when I work out and eat too much it feels like I am wasting my time there. So even if I only burn 300 kcal, I feel like I am taking care of my body and pay more attention to what I eat over the day.