‘chemically similar’ as in pharmacology, not chemistry. Like I said, I’m not a pharmacist so any explanation would be insufficient. Every drug source I can find compares methamphetamine, methylphenidate, dextroamphetamine, and amphetamine to each other. They all also produce the same metabolites. You’re technically correct when you say they aren’t meth, but I specifically brought up thc because I’m drawing comparisons to why it doesn’t actually matter; to the average person it’s all meth.