Sure, the prices of oil and natural gas go down sometimes, or grow more slowly, because of increased supply, but let’s look at the graph of oil prices post-WWII:

https://www.macrotrends.net/1369/crude-oil-price-history-cha...

The first big crash was at the end of 1985/the beginning of 1986, which Wikipedia says was due to falling demand (e.g. people consuming energy):

https://en.wikipedia.org/wiki/1980s_oil_glut

There was a temporary spike in 1990 after Iraq invaded Kuwait. I guess you could argue that the price went back down because the supply changed.

There was a crash in 1997–1998 that was partially due to increased supply but also due at least in part to the Asian financial crisis. The next big crash was from June 2008 to February 2009, again due to a large financial crisis. There was another crash in June 2015-February 2016 due to a stock market crash in China, and finally we get to the massive crash this year driving futures prices negative, which was of course due to COVID-19 reducing demand for travel.