Yeah, this is just silly. There's no way to compare the rush from IV amphetamine or opioids to what happens from snorting adderall.
The effect is so different you can't compare it as just a "lesser rush" because that's just not what it is.
Yes, you can really only get a rush from IV and smoking- that's the only way you'll experience that rapid flood of the drug to the brain. It's not something against intranasal use, but the absorbtion rate is just so much slower that it's worthless comparing the two.