Personally I combine both techniques. By incorporating engine braking I lessen the wear on brakes and get several other safety benefits.
By downshifting as you slow/brake you should be in a gear that allows you to quickly accelerate and maintain quick effective control of the MC should some one unexpectedly pull into your lane space or if you should need to make a quicker/shorter stop than expected. I.E. you can execute an escape maneuver to avoid a collision confident that you will not hear that KLUNK, KLUNK of the tranny and loss of acceleration torque and control you need to save your bike, body, and life. How many times have you had the light change to green while you’re decelerating, and needed to accelerate to avoid impeding traffic or worse yet stalling? Far better to be in the right gear to smoothly transfer from slowing down to accerating to speed.
The other benefit to using gears and brakes is to better control the MC. If you 'coasting' with the clutch in, and you encounter sand, gravel, water/mud and tug on the brake you WILL lose control and balance and likely go down.
Using engine braking brings the laws of physics into play. Since the engine braking causes more downward pressure you actually have more control and stability available to you.
For inexperienced (folks with less than nn,000 miles, or less than NNNN hours in the saddle) casual weekend type riders tend to brake for and coast through curves and turns. You should watch the supercross riders. They use engine braking to exert downward force to let them negotiate serious curves using physics. I use this technique even in town on normal roads. Combining inertia, downward force (gravity) good throttle control (engine braking). The technique works well for stopping also.
There is my two cents worth…
Ride safe & long,