I'll give you my take on the breeder's response, but please take this constructively.
No one crops vizsla ears, so if I were a breeder and got a question about that it might indicate to me that the person had not done sufficient research. Tail docking is a hot button issue that I happily remain on the fence about.
Having a different value on that issue than the breeder could be taken as a criticism of their choice to dock and even if it doesn't it is just a mismatch. This isn't a simple transaction, as I'm sure you're aware, so it's important to find a good fit personality and value wise as you enter into a long-term relationship with this breeder. I'm sure you can find a breeder that doesn't dock, but I would warn you from making that such a high priority on your list that you might overlook health clearances, good temperament fit, etc.
Mentioning Cesar Milan would also be a red flag for me. I like that he is aware of his energy and how that affects the dog, but overall his methods are too heavy handed and based in dominance theory, which doesn't give a breed as intelligent and sensitive as this one enough credit. They want to please and if you treat them with respect and love they will give it back 10 fold. He would look at a vizsla leaning against their owner and say it was asserting dominance over the person. If you followed his advice and discouraged that you'd be robbing yourself of a wonderful relationship and more importantly you would be taking away something that is bred into the very being of these creatures. What bothers me most about his methods are when he provokes a dog into reacting in a negative, but natural way and then corrects them into submission. A vizsla will shut down under that kind of pressure. Milan certainly uses some positive methods as well, but that's not what I think of when I hear his name. So we can disagree on whether he's a good trainer, but hopefully that gives you some insight into what the breeder may have been thinking.
I personally think you could make owning a vizsla work with the schedule you mentioned. I am also 27, live 10 minutes from work, and go home mid-work day to hang out with my dog. It works great for my adult, lower energy dog. A puppy however is far more demanding, especially during those first couple months at home. Many people take off a week or two to help transition the puppy and start training off on the right foot. If that's not an option then hiring a dog walker to come and relieve the puppy in the morning and afternoon is definitely something you should consider.
Again, please don't feel defensive reading this. I believe your views are more nuanced than my interpretation is, but it's worth seeing if they came across that way to this breeder. Puppy applications can only give so much information and I'm sure you can appreciate how difficult it is for breeders to make the choices they do.