The 3 milestone discoveries of the 2001 - 2010 decade for Theories of Romantic Relationships Development are:
I) Several studies showing contraceptive pills users make different mate choices, on average, compared to non-users. "Only short-term but not long-term partner preferences tend to vary with the menstrual cycle"
II) People often report partner preferences that are not compatible with their choices in real life. (Behavioural recommender systems or other system that learns your preferences are useless)
III) What is important in attracting people to one another may not be important in making couples happy. Compatibility is all about a high level on personality similarity between prospective mates for long term mating with commitment.
The key to long-lasting romance: COMPATIBILITY is exactly STRICT PERSONALITY SIMILARITY and not "meet other people with similar interests".
article: How successful is digital dating in finding ‘The One’?
Alexa shows an inverse spike after 2017 New Year's Eve for several online dating sites including Match, PlentyOfFish, Zoosk, eHarmony, EliteSingles and many more!