That logic is true in regards to 99% of supplements out there. Most people aren't smart enough to find out what sort of dosage, PCT to use with gear though. Many of the more garbage supps claim to give 'anabolic' effects though lol.
I don't think that pre workout is a bad thing when used sparingly. I couldn't take this stuff all the time, even if I wanted to, as I'd be awake all night, every night. I did notice on an otherwise average feeling day, that I could pump out the last 3 sets of DB rows easier or other high volume work for example. Didn't really make any difference to my 5/3/1 sets, though the lack of sleep was telling in my shitty results.
FWIW BN went on and on for ages about how their PW101 was more effective at helping during exercise than stim based stuff, they ended up caving - smartly - to market pressure for a pre workout that was stim heavy and gave 'the pump like caaaaaaaaaaaaaaaahmming'.
Protein powder is a convenience, nothing more or less, despite what supp companies want you to think.
I generally only have fish oil (jury still out on benefit), Vitamin D (office worker and white as f**k) and Psyllium husk. I can't find any conclusive evidence of multivitamins being good for anything, and I don't feel any different not taking them.
I actually think that many bro curlers will never get it tbh.