I think it was always a big deal and kind of a key attribute women consider for physical attractiveness, but it was kind of not spoken about in general and in the internet age cat got out of the bag on psuedoanonymous forums and things like that okcupid data analysis got shared.

It might be perceived as a bigger deal simply because it's a hard, objective factor. In practice though, there's so many other things you can do to improve your chances that there's no point in even thinking about it.

I am guessing it is more explicitly stated as a preference than in previous decades. And globally, proportionally, a lot more people are taller due to drastic decreases in malnutrition, so there are wider variations in height.

I keep hearing that online dating had elevated the importance of outward appearance - which would include height - even higher than what it used to be.

So do I. I've been with the same woman for the last 20 years but before that I had no trouble dating online and I'm definitely not tall.

The thing with online dating is filters kill a lot of opportunities that earlier you could compensate for. Most people and women can't easily tell between someone 5'11 and 6' and subconsciously someone who is dominant is perceived as taller than they are. But on an app, women will set a hard filter cutting out men at the edges who might have a chance earlier. Interestingly, women have ensured there is no weight filter, so things are further stacked against men looking for fit partners.