The first season was generally good. Each episode included important clues that contributed greatly to the plot and helped the story unfold without revealing too much. Together with a cast with great chemistry, Riverdale had seemed promising for a young/teen audience.
Overall, it was an easy to watch, generally interesting and can easily be binged. However, if you are someone who is a diehard Archie comic fan this is not the correct adaptation for you as it doesn't stick to the main and very distinctive character attributes that are shown in the comics.
Season 2, to me, was a massive let down. It did not live up the hype at all. The first few episodes introduced many different plot/storylines that they did not expand to a satisfying level and the eventual ending was very predictable and could be guessed very early on in the season. All in all, I stopped watching Riverdale very early on in Season 2, unable to cope with the poor writing that I thought was trying too hard to be 'woke' in order to stay relevant with its audience.
I refuse to watch Season 3 and have no clue as to why it has been repeatedly renewed.