I will never enjoy a game that requires very specific builds, especially in a game like this one that has a skill tree with millions of possible build types.
Path of Exile 1 was free to play and the idea behind this one was always going to be the same thing. They make a ton of money off of people buying cosmetics, inventory tabs, and other such things that make the game easier. I don't know how much a game maker can make off of selling a game for full access, but the makers of Path of Exile pulled down around $100 million a year for about 8 years, so yeah, free-to-play definitely can make a ton of money.
It's not going to be free for at least another 6 months, at the moment it is $30 but if you are playing it on PC that $30 is credited to the online store.
Honestly, if I had something else that I was really enjoying I wouldn't play this. I don't like games that never end and that is exactly what this is. Also, unless you are very lucky and have a seriously good internet connection, it is plagued with connection issues like rubber-banding, auto-pausing, and general lag.