You've misunderstood enthusiastic consent. There's a big difference between enthusiastically wanting to please someone without getting anything in return (I believe the term in lesbian circles is "stone butch") and yielding to someone because you feel guilty about something. Enthusiasm doesn't have to be motivated by a desire to orgasm or receive pleasure, it can be motivated by a desire to give pleasure.
I've submitted to sex because the alternative was him putting cigarettes out on his arms and telling me it was my fault because I wouldn't have sex with him. This was abusive. It escalated to me waking up to find him penetrating me, which is rape because sleeping people can't consent. I take an extremely dim view of people who try to pretend that guilt-motivated sex isn't abusive, because it is. If I want to apologise, I use my mouth to say "I'm sorry", not to suck his dick.
No, I don't think I have. Using the term "enthusiastic consent" in the way you are suggesting would be meaningless, or confusing.
The kinds of things you are talking about range from emotional manipulation to abuse, sometimes similar behaviours come out of personality disorders. It's not emotionally healthy, at the least, for people to give in to having sex for any of those reasons and in some cases it is coercion.
It's absolutely a good thing for people to understand that those are not healthy or honest behaviours and will not only likely have negative personal consequences but they will often lead to even worse relationship dynamics.
But the word "enthusiastic" really is not a particularly accurate description of a decision that doesn't include that kind of dynamic. "Don't have sex just to keep someone from self-harming" is not the opposite f "your consent must be enthusiastic" and it would be confusing and a strange use of language to read it that way.
I'd also point out that the idea of enthusiastic consent is used to advise people, particularly men, what they need to see in a partner. It's not enough for the partner to agree, or to avoid acting like an ass, to be sure the consent is valid, it has to be enthusiastic.
How is that supposed to be a workable standard? How do you know if someone is enthusiastic, or they don't have mixed motives for agreeing to have sex with you? How are you supposed to be responsible for what is in another person's head or how they express themselves?
There are all kinds of useful things that can be said about what people should think about when deciding to have sex, but saying consent has to be enthusiastic is not one of them.