The process is very straightforward, and yes you can most certainly fail!
Put in the requisite amount of study, application, and effort and you should (like most people who do) be fine. Don't, and you will quickly struggle, and it is going to fairly obvious to the individuals teaching and examining you that is the case.
I have always said that it is a "steep learning curve" for cadet pilots, and that is because it is! However, I have always been impressed by cadets because invariably they take it as a given that it doesn't get any easier and consequently they do put in the work and achieve a standard that is normally well up to that required.
The TR is most definitely not "a formality" which as a CTC graduate I am a little surprised that you should ask the question. You will most certainly need to be on top of your game. I have seen plenty of people fail though rarely as a result of not putting in the necessary effort. Given that these days the cost of type rating is often bourne by the candidate, it could become a very expensive lesson to learn. Also, given the competitive nature of airline vacancies, a failure is unlikely to be considered a badge of honour.
This isn't a "passenger perspective" although it marries entirely with the advice you have already been given.