It seems like overtourism is a regular topic in the media these days, and this article provides some interesting suggestions - https://www.ctvnews.ca/lifestyle/4-ways-to-be-a-good-traveller-in-the-age-of-overtourism-1.4443972 .
Even remote Mt. Everest has been "overtouristed" this year and the delays caused by the "conga line" to the summit was a contributing factor to the deaths of several climbers.