This  is quoted elsewhere in the Gemarah in Masechetot Nidah and Megilah. The pshat – simple meaning of this is that you do not have choices in your life when it comes the vast realms which do not fall into the Yirat Shamayim category. If you were born with tall, stupid genes you will be tall and will find it difficult to study. However, it is your choice whether you will believe in G-d and whether or not he gave us the Torah.

In Masechet Nidah there is a vague Tosafot which cites certain sources which seem to contradict even the small amount of free choice allowed for in the Rabbi Chanina Statement. They quote the following:

[King] Chizkiyah learned through prophecy that his prodigy would be evil. (Brachot 10) Therefore the wicked kings like Menashe who succeeded Chizkiyah may not have had free choice in being evil. The Tosafot use this as an example of the possibility that freedom of choice is not necessarily universal.

Tosafot continue to quote the Gemarah from the end of Masechet Shabat (pg. 156a ) A person who is born under Jupiter (Tzedek) will be righteous. (Tzadkan)…whoever is born on Shabat is called holy.

Is it possible that certain people do not have freedom of choice? Is this selective? Is it possible that it always applies? Is it possible that each person sometimes has freedom of choice and sometimes acts as a well programmed robot? Perhaps entertaining this question too deeply (more than just perusing this Drasha) is forbidden as part of the forbidden questions: Mah Lemalah? Mah Lematah? Mah Lefnim Uma Leachor? – What is up? What is down? What is inside and what is beyond?