I guess my thing is that me and my husband have spent four years building our relationship; she has only been around for seven months. I think by "putting us on even footing" that maybe she expects to be where we are emotionally, and I am sorry, but that won't ever happen. I may be wrong for saying that, but I do not know how else to put it.
Okay just for myself, when I read that I didn't see her saying they will NEVER be on equal footing. Only that they will not be in the same place emotionally. I am of two minds on that, personally. DH and I have been together almost 20 years, married going on 17. So yes, there is a lot of history, a lot of emotional work, and a lot of things we have gone through together, worked through together, that a new relationship just won't have. So no, not on the same emotional footing.
HOWEVER, I don't think any two relationships are on the same emotional footing. They are two different relationships. That doesn't measure how much you love someone. I love both my men equally in amount. (if you are going to try and measure) The two relationships are just different. No, I am not as 'attuned' to DC as I am DH, but that comes with time and the gap between how long I have known them each intimately is large. Can it be overcome with time? Yeah, sure. DC is learning more about me faster than DH did. Not because he's a savant, but because *I* have had time to know myself better. To be able to express myself and my needs, flaws, issues, quirks better.
So yeah. . . no need to be all confrontational. I think people read things and put their own emotional spin on it. Just as OP did with the 'wife's' post. She saw the negatives but not the positives. We read things with our own emotional baggage not with the posters.