That’s why you hire market analysts and consultants and whatnot. Sheesh, just watch Extra Credits issues regarding F2P. It’s pretty much in glowing neon there.
You can’t just say “Let’s put some restrictions of everything and make non-paying users suffer”. You just don’t, unless you want to fail miserably.
The moment you decide you want to monetize the ABSENCE of suffering you jump happily off a cliff.
Premium stuff is supposed to be “better than free”, yes. But vast majority of the F2P playerbase is (by default) NOT inclined to buy ANYTHING. They want to play the game, see if it’s enjoyable and then, MAYBE, cough up some cash to make it MORE enjoyable. The moment players face a paywall that says “Pay up or SUFFER” they start looking for another game.
TL;DR: Yes, F2P developers need money. But before that, they need to come up with stuff players would WANT to pay for, not stuff players MUST pay for to make their experience less frustrating. And so far, it’s been going the wrong way with trade restrictions.