First-person romances are generally found in YA and NA. Older romance readers are often turned off by books that aren't third-person, from both perspectives. I'd keep that in mind. It doesn't mean you can't sell an adult novel in first-person, but agents and publishers might be more reluctant to take it on.
Ignore that article. It's one of the most insulting, patronising things I've ever read. Plus, it assumes all readers in the world are from America (specifically, the US South). Yeah... no. I'm certainly not.
The best way to learn how to write romance is to read heaps and HEAPS of books in your subgenre. Yes, learning craft is important, but not when it's written the way this article is. I mean:
When you write a romance novel, you start out with one big advantage. You already know who your reader is: it’s a woman. To be more specific, it’s a middle class and middle aged woman from the South. They like ice tea and hot romance...
As a romance writer who certainly doesn't approach her work that way, I'm so offended by it.
I don't see a name for who wrote that article. So I can't even get past step one of "do I care about your opinion", which is "can you do the thing you are trying to teach".
Exactly. The person who wrote it is approaching the genre with a great deal of contempt. Articles on writing romance - written by people who actually know what they're talking about - can be found for free on blogs like Romance Writers of Australia (the American one is behind a paywall), and the Romantic Novelists' Association (a British organisation).