Interesting thread topic.
I grew up in a Guardian-reading family in the 1980s and 1990s, when the "New Man" stereotype was being pushed quite strongly. So, there was lots of encouragement for me to be in touch with my emotions, and to express them; and I heard and read lots of explanations about why this was better than traditional forms of masculinity.
I now think I was sold a pup.
The girls I grew up around weren't interested in men like that: they considered them sooks and wimps. In my view, they regarded showing emotion as unmasculine, and while it might be a fine trait in a friend, it wasn't a good one in a boyfriend.
Not showing emotion shows strength, and the strong, unemotional, protective man is a very deep-rooted stereotype.
I've now been married for nearly two decades and DW, unfortunately, has had problems keeping employment, psychological issues, and problems with her physical health. I have had to bear the brunt of her frustration, much of which has been taken out on me. Learning traditional manly stoicism has been extremely useful for getting her and me through all that. I would say that the New Man ethic of showing emotion has, for me, been an entirely useless guide for life. Instead, I have learned to be aware of my emotions but also be very good at not showing them, because it is often a luxury I cannot afford.
As others have rightly pointed out, there are other ways of showing love, e.g. through acts of service, but that is not what the OP was about.