Young green/raw/sheng pu'erh is very much like green tea, though in many ways it is smoother to drink (the finish) but it can have a certain harshness to it since it's sometimes meant to be aged. I could see a green tea lover thinking it was "very bad" green tea since it can be so harsh and grassy. But, there is so much variation... So, don't let one cup make you give up.
One of the nicest teas I've had so far was about 5 years old, it still had greenness to it, but it was softened from the beginning of aging.
Old/raw/sheng is so different from young/raw/sheng they are on different planets. It can be musty and complex, earthy, and it changes every time you steep it. This is "the good stuff" IMHO. It's the kind of tea anyone would like (unless you hate things that have the aura of age and history to them..) Honestly, it's both addictive and expensive. I warned you.
Then there is cooked (shu/ripe) pu'erh. It is very flavorful rich chocolaty, but a bad batch might taste like feet or fish. (avoid naturally) It's cheaper. I've had some really lovely shu. And some really bad shu. It's a gamble but at least it's not an expensive gamble.
And just to confuse you there are white pu'erhs and green pu'erhs.
It's a complex landscape!
I'm quite new to drinking this tea, but I think there is just so much to explore. Try a bit of everything!