What SGB said. I would like to think my view is tainted by my long history of truly awful relationships, in which I was fully committed. I certainly 'worked' hard at them: read "sacrificed myself to them". Then I see zillions of threads in Chat and AIBU; I hear the women down the shops; I realise that the majority of women are making disproportionate sacrifices to their relationship commitment.
Being single isn't so bad. I agree that 'commitment' is oversold to women. Being in an equal, balanced, happy, mutually supportive relationship is ideal - but singledom is a better alternative than commitment to an unequal partnership.
From a more distant perspective: I was a fan of Helen Gurley-Brown (inventor of Cosmopolitan) overall. On reading her obituaries and memorials, I am reminded that, when she advocated "Having it all", she never meant this for women with children. She meant, simply, the Cosmo life of a satisfying career, good friends and plenty of great sex. She assumed that a Cosmo life was so good for women, they would only give "it all" up for the ideal relationship, with children. Sadly it didn't work out that way and her magazine is now little better than a "How To Get A Man" manual.
She wasn't wrong, though. It's usual for men to focus their energies on career, friends and great sex. If they decide they want kids, it's usual for them to seek a woman who will make an efficient family partnership. The business of "full commitment" is less consuming, to most men, than it is to women. In my opinion, this actually leads women to sacrifice themselves on the altar of The Relationship, unasked and often unprompted.
In short, sl34, a fully committed relationship would be one where mutual respect is complete and equal; where goals and labour sharing are clearly set out on equal terms; where both parties are equally flexible and considerate, and where the commitment has been openly discussed and honestly made. I don't see too many of those tbh.