i started playing at the end of season 3 and game had an average lenght of 45 min instead of 30 minutes, and not that you had longer boring times during games, a 30 min games rn is ended quite quickly and 50 minutes games are the most fun, while at that times game of 55 min were late gamish feeling and the longest game ive played was 1.5 hour (only once tho)
but what made people love it season 3 the most was that at the time, even if the game was a 5v5, if you are good enaugh, you could carry
and its not (champion is so broken that he can just right clic and 1v5) it was; if you are good enaugh you can turn a game upside down, but only in a good way.
its hard to explain why exactly it was so fun to someone who didnt experience it but a single enemy that carried their team wasnt like today where is just so overpowered that you can 1v5, really felt like no matter how bad you kda is, you could help and no matter how good enemy is, there is always hope