As a kid in the 70s, it was required viewing. We never missed it. The quality of some of the songs was fantastic. A number of great singles {like "Power to all our friends", "Beg, steal or borrow", "Long live love", "Waterloo", "Ding a dong" "All kinds of everything"} in the UK charts during the early to mid 70s came from Eurovision. It was like "Miss United Kingdom" and "Miss World". We never missed them. Looking back on it, I find it interesting that we found such pap interesting, but we loved competition and arguing !
Eurovision was frustrating because it meant the football would be on later than usual on a saturday and even though it was once a year, I was busting like I wanted to go to the toilet. I could not wait for it to end. But I also liked it so it was kind of paradoxical. The last one I saw was in 1983.