Scalp Shampoo Scrubber changed my hair

I recently bought one of those cheap scalp shampoo scrubbers. No particular brand, just one with simple silicone teeth. They're sold all over Amazon etc. This simple scrubber has changed my hair and scalp. I have fine medium density waist length hair. My hair has always been flat, limp and oily within 24 hours of shampooing. I've struggled on and off with mild scalp flakes for many years. I've tried to stretch hair wash day for many years, because my ends are dry but could never get past two days without shampooing. My hair was just a disgusting oily mess after 48 hours. All dry shampoos I have tried irritated my scalp skin, so dry shampoo was only for extreme hair emergencies.

I originally tried the scrubber because it looked like it would feel nice as a head massage in the shower. It does indeed feel very nice in the shower. However after scrubbing my scalp, I get out of the shower and my hair and scalp have never felt cleaner or better. Suddenly I have volume at the roots. Suddenly my scalp feels airy, clean, tingly. I didn't think I had oily hair after showering previously, but now my hair and scalp are CLEAN. I'm sitting here 48 hours after a shower and my hair and scalp are still clean, not oily, light and fluffy. Last hair wash I was able to go 3 days without washing my hair, but I think I could have gone 4 days had I not gotten a bunch of body oil moisturizer in my hair on accident. I think I'm going to attempt 4 days again. I have not changed any of my shampoo or conditioner products. I want everyone I know to try one of these. My hair and scalp feel so much better.