If you use your developer tools and search for site-navigation, you have some css that is hiding this block as it is still within the page code.
The site navigation is not what I am having trouble with it is the BuddyPress profile navigation bp-nav which doesn’t show up in the developer tools, except for the sub-nav one.
Also, I forgot to mention, if I change that nav to verticle or tabbed it still doesn’t show up.
ahh apologies, not sure why the top nav didn’t load for me on one of the pages.
Have you switched themes to 2019 or similar to ensure it does appear, if it does do you overload any files in your theme? Alas this isn’t my area of expertise, although little is 😉
I tried the themes 2020 and 2021. It doesn’t show up in those themes either.
I have only made changes to CSS, not template changes or overrides