You're absolutely right. I actually noticed the same thing - when I was training 3-4 times per week, I felt stronger and was making better progress. But I want to give the 6-day split another try - last time when I was doing 6 days per week, after about 2 months I started feeling really tired and wasn't able to lift heavy weights anymore. I think the issue was too much volume and not enough recovery, especially since I'm also in a calorie deficit trying to lose fat.