The answer in short is that it entirely depends on the lifter, how long they have been training, what their other commitments are (how much spare time they have to dedicate to training), how old they are, how far out from competition they are and several other factors. 

The things to consider though are that to achieve a goal you should preferably train at the optimal frequency to facilitate progress in your lifts, which is not the same thing as training as much as possible.  If you can get good results from training 3 times per week then why train 4 times, other than for enjoyment’s sake.

The problem with training more times than necessary (in too early a stage of training) is that you negate the possibility of adding to training frequency when you reach a sticking point / plateau with your lifts.  

Don’t exhaust all your avenues of potential plateau busting, before you actually need to use them.  In short, take the simplest route to your goals, and don’t overcomplicate things. 

With all that being said, do not make the mistake of thinking that you do not need to spend some decent amount of time each week dedicating to learning technique and you of course need a certain amount of volume to be able to give enough stimulus to grow stronger. 

A good starting point is 3 sessions per week. Start with that and see how well you recover between sessions. 

Build up your session density (amount of work performed per session) and monitor your progress.  If your progress starts to stall once you have tried a few options to allow more progression then you can look at one option of adding an extra day but always be aware that you must always ensure you monitor your recovery and check that you can handle the extra work.

Firstly remember that no movement in the gym (unless you are a weightlifter, powerlifter, strongman or similar) exactly replicates or can even come that close to replicating your sport.  The term sport specific training was hijacked by the personal training industry and gave a vast number of rather blinkered PT’s the seeming right to distribute a whole series of alternative exercises, whilst moving away from the tried and tested basics,  in favour of overcomplicating movements to make them seemingly move impressive. Arguments were made for squats on a swiss ball and squatting on a boss ball being more relevant to a contact sport for example because it encouraged the trainee to ‘engage their core’.  

Quite frankly a vast majority of these arguments were invalid and made especially by individuals who had never lifted a heavy weight in their life. You try and squat double, 2 1/2 or even triple bodyweight or more and not ‘engage your core’ (a term I hate and would rather people simply used correct terminology and said ‘bracing’ or creating intra-abdominal pressure).  

The reality is that gym training, with the exception of certain strength sports, cannot replicate your sport and trainers should not pretend that it can. 

Gym training for an athlete is G.P.P (general physical preparedness), and should be used as a tool (one of many) to improve performance. With that in mind, gym training must utilise safe, effective, quick to learn exercises which utilise muscle groups in a way in which will be relevant to some SIMILAR movements performed in the sport.