It's only forced in the sense that, by simply being nice to him, playing as a male Hawke you will be confronted with a dialog wheel response tree consisting only of "Flirt with" or "Completely end any pretense of a relationship" responses (this may be true while playing as a female Hawke as well, but in that case I was actively trying to pick those responses so I might have "pre-empted" it).
Or in other words, Anders, alone among the various npcs you can "romance", actually initiates that conversation himself, even if you were not necessarily trying to flirt with him, and forces you to make a decision right away (and not flirting back gets you rivalry points). Isabella might be far more openly flirtatious pretty much all the time, but she doesn't force you to decide to start pursuing a romance with her or shut her down completely in the second bloody proper conversation you have.
So yes, I guess I would say that his romance felt forced, because all of a sudden through no desire on my part my male character was being hit on by another dude. With Fenris, the option is there but you have to actually pick it first, if you decide to pursue that it is clearly your decision; with Anders they've coded in a "decide your character is a homosexual/bisexual" or "stay straight/just not into Anders and get rivalry points" conversation gate, which is really kind of stupid - there should absolutely be a way to be nice to the guy without making players playing a male Hawke as a straight male pick the jackass response to stay straight in-game. The way it is now, Bioware seems to equate "being a straight male" with "being a jerk" - as a straight male myself, that kind of offends me.
So yeah, it's not so much that the designers pushed Anders onto the player, it's that they force the issue of whether or not your character would even want to consider a relationship with Anders onto the player, and don't give you a nice way to let him down.
