Is Fortified Port wine any good?

There are a variety of ports (all fortified) that taste different one from the other...

Ruby port - the cheap stuff you pick up anywhere. It’s almost always very sweet and cloying. I generally use it for sauces (sweet and savory)

LBV - late bottled vintage - less expensive than vintage port and not quite as good, but much more refined than ruby port. Fairly reasonably priced and don’t need to be aged (actually not meant to be aged)

Tawny port - aged in wood giving it its tawny color. Generally made/labeled by how long it was aged (10 year, 20 year, etc.) Much less fruit than other ports- almost a nutty flavor. Pairs with desserts with caramel, nuts, pears. Not as sweet as Ruby. I really like tawnies.

Vintage port - this is the biggie you hear about. Only released in years when the harvest was really good. Meant to age for decades and decades. And really damn expensive. If you have an opportunity to try some, I’d highly recommend it.

There are a few others, but those are the main ones. 

If it isn't fortified, it isn't port. And yes, some ports are delicious, IMHO. You might not think so.

Don't you have homework to do instead ?

Some people think liquor tastes like candy. They mean cordials which might be 15-20% alcohol. Ol' Grand Dad brand bourbon tastes like gasoline, even to old, drunk, grandfathers. Wines can taste like many things including good old grape juice. But the missing niche is fortified wines, of which port is one common classification. A grape juice with a serious kick, often very old, 10-20 years vs most cheap wines that are only a year old, ports are mellow, complex, often elegantly sweet, and often with a distinct creamy undertone even when not officially a cream sherry.

Fortified wines tend to fall into the desert wine category having them have to be able to stand alone where other wines aren't terribly great if not paired correctly. One dramatic example of pairing is obsidian stout. It is bitter as battery acid, which is wonderful with sickly sweet deserts.

It definitely can be, but you pay a small fortune for the good stuff

All Port wine is fortified. The fermentation process does not provide sufficient alcohol. So an extra amount is added at the end to meet the standard.