I generally drink either whole or 2% cow milk in my coffee. Never added sugar, but sometimes half and half or the occasional oat milk phase instead. When you switch exclusively to oat milk for a while, it grows on you. I like oat as the best overall plant milk for coffee, and the Planet Oat original unsweetened in particular as you’ve heard, but it’s definitely a different product with a different culinary experience than cow milk.

But of course it is. Goat milk is also a different culinary experience. It tastes like goat cheese, which is maybe unsurprising but also rather unwelcome in coffee. Each alternative is rather different.

I mostly drink coffee at home. I grind beans one or two scoops at a time immediately before use and brew hot concentrate with an aeropress then dilute to black (americano-ish), but my milk preferences are the same in an occasional expensive coffee shop latte. Oat is the best alternative option. You’re right that it’s not as potent, and I tend to use even more oat milk in coffee than my somewhat heavy pours of cow milk.

I haven’t done careful investigation, but I suspect oat milk has a better balance of impacts on personal health and environment than many of the plant-based options. Almond milk production, for instance, takes enormous amounts of water out of the aquifer under California’s Central Valley, whereas oats are widely grown. Soy milk is controversial health-wise. Oat also tastes better to me than both of them. Coconut is okay but has a somewhat strong flavor and thin texture.

As a highly-engineered food product, you should expect substantial variation from one brand to the next. Try several.