At 47, I can't eat like you suggest, and have meaningful gains. I must eat clean, and watch how many calories I'm consuming per day. There's still some room to play, but fat does not shed as quickly, and it cost me in lean mass to reduce. I eat less than 2000 calories a day on average, and I'm getting stronger and growing. I estimate my lean mass to be around 142lbs, current weight 173lbs. I eat for my lean mass, not my bodyweight.
In the last 6 weeks I've managed to keep my weight the same, but increase my workload slowly. As of this week, based on how I'm feeling, I'm at my max workload. I will probably need to cycle to a different rep range within a week or two.
When I was a teen, I could, and did eat everything in sight. Even into my mid thirties I could eat a lot more than I can now. Getting oler doesn't suck, but you need to pay attention to diet better. The margin for error gets narrower.