When you say this is unbiblical, what do you base it on? What scripture do you have in mind?
I certainly believe that both husband and wife should seek to please each other. I Corinthians 7 states that they do. If a man loves the Lord and loves his wife, he should have some respect for his wife's desires. A lot of these decisions, like going to medical school, are things a couple really needs to pray about and let the Lord guide them on. It is not just a matter of our own desires. Medical school takes years out of your life and could send you in a different direction from where you would go otherwise.
But let's say I think if a man tells his wife she can't go to medical school, the man is being overbearing and controling. So if the wife in this scenario asked me for advice, what should I tell her? I should tell her to submit to her husband. That is what the Bible says. Even if a husband does not obey the word, his Christian wife is still supposed to submit to him. She is supposed to have the ornament of a meek and quiet spirit. She is to be like Sarah, who obeyed Abraham, calling him Lord. As you pointed out, Sarah obeyed Abraham when it got her married off to a foreign king. Abimelech took her into his harem, apparently, but hadn't had a chance to sleep with her.
So what can a wife do if her husband is being controlling and not considerate of her desires? She can pray. God is her defender. Does that sound unfair? Does it sound hopeless? No, we have a mighty God who listens to the prayers of the saints. God took care of Sarah. He didn't let the king sleep with her. He struck the household with illness and barrenness and gave the king a dream. Sarah left unscathed. Peter taught wives to submit to their husbands like Sarah, whose daughters ye are if ye do well and are not afraid with any amazement. Women should not be afraid to submit to their husbands.
If a woman has a dream to go to medical school and it is really a big deal for her, it could be she just has a dream or desire that she is holding on too much and needs to surrender it to the Lord. It could be her husband's resistance is something the Lord is using to help her come to a point where she can do this. If she has a child while in medical school, who will take care of the child? Medical school involves an insane amount of hours, not just schooling, but residency afterward.
If I were talking to a man who was I thought was being overbearing towards his wife, controling her, and not letting her fulfill her dreams, I might encourage him to seek to please his wife. Even if he isn't a very good husband though, that does not negate the wife's obligation to submit to Christ by submitting to her husband.
Not going to medical school or majoring in tax law instead of some other kind of law is not the same thing as the husband shaking a little baby hard every night. It is not the same as when an army of 500 men is about to come and kill your husband if you don't feed them. It is not the same as your husband trying to get you to smoke crack and rob a bank. There are extenuating circumstances in life where a woman may be faced with "Do I obey my husband or obey this other command from the Lord"--with as submissive attitude toward her husband as possible.
My wife didn't want me to learn to ride a motorcylce in Jakarta traffic (where those lines on the road mean very little and where if someone wants to turn you cut them off and don't ever let them in). I gave in to her request. If I died or were injured, that would hurt her, and she cares about my safety. I don't want her to worry. I love my wife, and it is right that I should love her and seek to please her as my wife.
I am in graduate school and have been for a number of years. I believed this is what the Lord wanted me to do, and my wife also prayed and before we made moves to each of the schools, we were both in agreement that we believed these were the schools the Lord wanted us to go to. I want my wife to be on board on these decisions. Though my wife hears God on all kinds of things, I got direction on these decisions first. I would pray for the Lord to tell her before I mentioned it to her, but I had to offer the leadership and start moving in the direction first, and then she would pray and get confirmations about it. It wasn't a war between us, though. We were seeking God's will.