The corollary is, you have to be giving it away in the right place. You’d think that would be Medium.
My business adviser side is now going to pop out. Who are your customers? Who do you want to sell your writing to? Are they shopping on Medium? Customers aren’t necessarily the same as readers. As you say, the guy you sold the TV pilot to bought it from a spec script you sent him.
But after he received your piece, he then read your material on Medium? Then Medium is like your website or LinkedIn page. No matter how people learn about you, they will immediately check you out online.
So if you remove all your stories from Medium, that might be like taking down your LinkedIn profile — you disappear. Potential buyers wanting to check you out can’t find you.
It’s unclear to me how you hurt your chances to sell big pieces of writing by continuing to post your stories on Medium.