Well… that’s a tricky one.
Short answer: No.
Like he says, it’s a training to improve your health and fitness. That’s always a good thing. It depends on the state you’re in if it will help your performance on court directly, but chances are that you will at least feel like you play better and you’ll be able to play at the same level for a longer period.
But it’s the opposite of what a badminton player should focus on if he’s already healthy and kinda fit. I’m Badminton you have short intervals (rallies) way above your maximum aerobic heart rate, close to your (overall) maximum heart rate. Unfortunately that guy kinda messes up those two in between when talking, because for him, talking about that training, the maximum heart rate refers to the aerobic heart rate. When playing badminton, your heart rate will only drop to the aerobic range between rallies.
Badminton needs your muscles to work with the stored energy inside them, needing then and the rest of the body to refill that storage quickly between the rallies.
This training is meant to increase the power the muscles can produce without going to the anaerobic energy cycle. It also will help your metabolism adapt to that. It’s a classical endurance/stamina training.
Like you can see, those two things are quite different and a badminton player already does train the stamina in many different ways, during the breaks between points, warm up (can easily be 40 minutes or more), cool down, recovery training, … so not a ton is needed to add to that. You can say that this training is a great foundation to build up on, but it’s hard to say if it’s really all that easy to get back the speed on court.
If you want to dig deeper, learn about the different muscle fibers, different ways to train a muscle and metabolism… and I’m almost certain you’ll learn that training is more about opinion than about hard facts. Just like the above is an opinion. A guess. I cannot give you any study that actually tried to find out about the usefulness of this kind of training for (recreational) badminton players, let alone other studies to confirm that. I know that in many sports very different training regimes did yield comparable results in the past, so to add more opinion: If you enjoy the training, do it, care about the badminton shape later (but before you get back on court) or add in more badminton specific training in between. It’s certainly better than not doing any sports.