That is what I believed but what I saw seemed to conflict: Install the Tor Project browser, connect to an .onion host, then click on the icon that shows the route. It appears to show the route goes through non-Tor hosts (I don't call them 'clearnet' because I expect the data and some metadata is encrypted).

EDIT: See this screenshot from an article elsewhere in this discussion. The blacked out bits next to "Portugal", "Germany", and "United States" are publicly routable IP addresses (IIRC):

https://www.jamieweb.net/blog/forwarding-tor-hidden-services...

This is normal: your computer picks the set of 3 relays you want to use, hence it knows their IP addresses. The 3 relays from there to the hidden service are not known to your computer though, so those are just listed as "relay"

Thanks.