I don't think anyone needs to eat as much as 3,500 calories per day in order to grow muscle. You can grow fat on that number, but there is nothing that suggests that your muscle volume will increase.
Everyone has their physiological limits, the plateau that they will inevitably hit due to normal human growth capacity. Some will find that genes dictate how much they grow, while others will defy the laws of physiology by introducing steroids and growth hormone into the mix.
Naturals reach their limits after various years of training and proper dieting. They then graduate into hormone use and slowly, but surely will reach their limits as well. Those that push too hard, could end up causing problems for themselves. After all, there is only so much the human heart can sustain.
Hopefully, one of our resident experts in human physiology can chime in on this.
"1"
I maintain at 2700-3000 calories currently @ 73kg bodyweight...You would be surprised how many people out there need 4000+ just to maintain their bodyweight. "Fast metabolism" is bullshit as well, it's just about amount of muscle and intensity of your training. Deadlift two times per week, squat 4 times per week with high volume, olympic lifts 3x per week and your energy expedinture will go through the roof. Give me 4000+ and I will just get fat.
There are genetic wonders, very few of them, who just won't gain fat no matter what but for everyone else out there, it's a simple matter of how heavy your workouts really are and how much muscle tissue you carry.
Surplus depends on what you take, if you are natural or on hrt anything more than 300 calories surplus is an overkill. Train to get better in the gym - more sets, more reps, more weight and you will add muscle. Never focus on your bodyweight.