I'm not rich so I can't purchase premium coffee and tea, for long I have been buying stuffs from the local market. Sorry if I sound uncultured not knowing premium brands.
I like my coffee plain, no sugar no cream whatsoever (I can tolerate cream more than sugar)
Sweet coffee is blasphemous, plus sometimes they add too much sugar. In my family only me who drink coffee like that. It's also a bit hard to find sugarless bottled coffee you can drink on the go (which actually taste like coffee and is not sweet) so I sometimes bring it myself.
As where I live, there's variety of local coffee. My favorites are Bali (sweet taste) and Toraja Kalosi (stronger earthy taste). Currently I have stock of Flores coffee from my friend who came from there, I usually cold brewed it or use a french press (no money for coffee maker).
For tea, I usually drink it plain whether it's black tea, green tea, or white tea (it's more expensive though). For green and black tea I especially like stronger taste, I let it steep for long so it comes as bitter.
I also enjoy milk tea and boba tea occasionally as exceptions, though I often feel sick after drinking those and regretting it (It's too creamy, sweet, and heavy that I want to throw up). For Thai milk tea, I only enjoy the one I made myself.
I like flower tea (rose, chamomile sakura), fruit tea (mango , berries) and spice tea (like ginger, chai, or lemongrass tea) too. I even sometimes add sugar because some tastes better with it (not too much)