Rob said the opposite, and I agree with him. It's mostly about luck, not hustle. A degree in business studies is of no help here.
This is not how it works. Gallerists have no interest in artists 'reaching out' to them. Keep the flyers for commercial prospects.
Sorry, this is simply not true!
I know and have attended workshops on the business of fine art photography given by successful galleryists. (I am an ASMP member and my local chapter has given talks on this, which is why I attended even though I am not a fin-art photographer.) Although there may be a few loud galleryists that scream they dont want flyers, just like there a few loud art buyers at agencies that scream the same, and stand out because of it, many get to know and become aware of fine art photographers they show by flyers and emails and networking.
And if you bring up and ask about the loud anti-flyer gallerists with the successful ones, most of the time they simply cant understand why anyone in the business would be like that. It is one of the main ways they find out about good artist worth showing.
Artists are not magically discovered by sorcerers. They are introduced, self-introduced, in almost all cases brought on by good business and marketing practices.
To add my own personal experience to this, I have reached out to several people in the past 12 years of being in business that simply told me that were not interested. Like a good businessman, I did not take this to mean they are not ever interest only not interested right now, and I persisted by following up every now and then, staying on their radar. Then, one day, I called and just like that they had a project for me and became great clients. Same thing happens with artist showing in galleries. If you only ever introduce yourself once, of course you'll get nowhere.
Insofar as Rob's comment on luck, I am sure his intense hustle when he was younger introduced him to people he was not planning on ever meeting that ended up giving him gigs. Although these chance encounters were "lucky," without his networking or marketing efforts, they would have never happened.
This is how all marketing and networking works, hence old business adage, "the harder you work, the luckier you get."