Hey thanks for the link!
Interesting, he doesn’t seem to be using any voltage regulators or capacitors for the servos. He also doesn’t seem to be sharing the ground between the servos and arduino in the illustrated wiring diagram
I recently made a project with 4 MG996Rs and they slowly all fried even though I was giving them all regulated 5 volts.
Running them off the breadboard fried the breadboard too due to the high amperage of the servos. Still doesn’t explain why they all individually fried though.
I posted another post about the extra regulator bug and someone responded a pretty fast with the solution that might be helpful to you.