I had to look up Love Island as well, and saw the above post ^^ and I can think of 2 precursors.
Girl Friday, a survival programme featuring Joanna Lumley, where she had to live by her own means on an island just off Madagascar for 2 weeks. Mid-90s, 1994/5.
I'm a Celebrity (get me out of here) is the love child of Girl Friday and Big Brother. 10 or 12 contestants on the island, again survival is key, and they get voted out one by one like with the Big Brother house. Last man standing wins the series. Been running since the early 2000s.
Love Island seems to be the match maker version of I'm a Celeb.