Sorry, I knew it is a risk that everyone gets different results on Google. For me the "featured snippet" is taken from this page, which was obviously generated by an LLM, and which plainly states that Phelps is 14 feet tall.
To me, it is a signifier that the web is truly dead, and LLMs killed it. The search engines are featuring the LLM outputs now.
https://www.scienceabc.com/sports/michael-phelps-height-arms...