Yes, if you sit for such long hours each day, then an ergonomic chair is a necessity. It helps to reduce the stress upon your back neck also joints. Since it acts thus, extended sitting spells turn more pleasant and cause your body less harm.
Even though you feel fine now, silent strain is put on your posture when you sit in a basic chair for hours. This causes aches, stiffness, or more severe discomfort eventually especially in your shoulders and lower back. An ergonomic chair gives benefits beyond brief comfort. It is all about the long-term state of well-being. It is about protecting of your body from the habits of poor long-term sitting.
Long sitting hours add up and your chair matters more than you think

Sitting for extended periods can quietly wear down your posture along with energy, especially using the wrong chair. An ergonomic chair keeps your body in balance. It keeps you supported during all day.
If sitting for long hours in a chair with poor support happens gradually, it builds up strain that you might not notice right away. Your posture can be affected, blood circulation can be reduced, and discomfort can be caused, lingering beyond the workday. Soreness could begin to affect you later. Even in times when you are not sitting, soreness might begin to arise.
An ergonomic chair is designed for these long hours. Your lower back can be supported, your spine is able to be kept aligned, and pressure points are able to be prevented. The difference after the first hour may not be obvious but after five days a week and eight hours a day and your body will thank you.
Comfort and focus go hand in hand during long work sessions

When your body is properly supported, constantly shifting or adjusting will not be much of a focus. An ergonomic chair keeps you productive because it provides comfort.
Have you ever found that you fidget, you lean forward, or you adjust your position just to stay awake or ease a cramp? That’s usually a sign. Your chair isn’t giving you good support. Mental focus is harder when your seat isn’t a comfortable one.
An ergonomic chair is what reduces the need for you to constantly reposition yourself. You can sit comfortably and stay focused on the task that is at hand, not on your own discomfort with proper lumbar support that is given by an aligned backrest and with a seat that fits your own body.
An ergonomic chair is undoubtedly helpful if you sit during long hours. Indeed, it is necessary for your health. Your body can stay supported, also your mind can stay focused, and then your energy can stay balanced much better through work stretches.