I'm curious how long has the Galapagos help the title of highest rated WHS on this website for, also what were some other sites that once held the top position

The Wayback Machine is your friend.
https://web.archive.org/web/20200807151304/https://www.worldheritagesite.org/ranking/community

I did not look at all the later dates, but it would surprise me if it wasn't Galapagos. The ratings are pretty stable.

I remember I've seen Rapa Nui in the 1st position in the ranking of most popular site. It was in summer or autumn 2019. I don't know how long it was in the top.

There is an argument that both Kamtchatka and Socotra score higher having clean 5* ratings by 5 and 7 people. We only penalize them for their lack of ratings. Initially, we didn't weigh it as hard and Kamtchatka came out first.

I feel galapagos is a deserving number 1 however I feel the penilization on lack of reviews is a bit too hard and that kamchatka should be ahead of rome and petra with current statistics