I wouldn't say that you're not good enough or that you need to be more of something. For one, I don't know you at all and so it's hard to say what your strengths and weaknesses are and how to make them "better". I use air quotes for that because even that is subjective as it often leads to loops of constantly improving and then your partner ditching you because "you changed".
Because of that, I don't think any significant changes in people's lives need to happen in order to get a partner. A lot of the suggestions I mentioned in the article tend to lean towards mindsets and shifts in attitude.
Those are small changes but they are significant. What I was implying is simply that.
Mindset is everything and how you choose to look and approach something will affect plenty of parts of your life. I'm not saying you need to meditate or do yoga to enter a calm state. But if you're running into issues then it's worth playing over scenarios and asking yourself what you could've done differently and how would things realistically play out.
If women are finding you boring because you're too caring and being your authetntic self then chances are they're not ready for something serious, even if they say they are looking for something serious. In my mind those are great qualities and it's not like you can be more caring or more authentic. People want to be treated as people in the end and showing compassion and care is one way to go about that.
If you're in a bit of a rut with dating then it might be a sign to take a small step back. Run those scenarios I mentioned, find a hobby that gets you outside more and meeting people.
I treat dating similar to sales because you're effectively selling yourself to a relationship. In sales, the owness is on the seller to look the best, but also to qualify the buyer. The qualification is to ensure the buyer is their target audience.
From what little I know from the few sentences you've posted, my guess is you've been qualifying poorly. And that's okay. You don't know any of these women and no amount of big improvments on yourself is going to change that. You can't improve your way into someone's heart. All you can do is once you begin dating, make changes then to ensure the relationship stays entact and healthy. If your other half isn't committed to doing that, that's their issue but they'll never admit that.
I believe at this point you simply need to find the woman that will do this. Naturally, that's easier said than done.