I didn't use supplements much, but lately have just been messing around with a bunch, partly out of boredom, but partly to see if anything changes.........most of these are powder form from Microingredients. YMMV but here's my thoughts:
Creatine: actually does what is expected. Price has gotten stupid
D / Zinc / Quercetin / C - was my covid plan....got covid, got over it. Still take it daily. Have no idea if it does anything, but cheap and safe.
Glycine / Magnesium Glycinate - I find this does actually help with sleep. Not sure which one does it. Mag Glyc tastes like absolute shit
Vit K - no idea
CoQ10 - no idea, but if you're on statins, it's recommended. If I go off them next year, we'll see.
Tongkat ali - will get T level checked in Jan to see if it had impact - no idea but feel good
Lions mane supplement for coffee - no idea....but like the taste (coconut) and got it all half price.