seo – Internal links to pages vs. sitemap.xml links to pages

I have a page that has no link to it, but is listed in sitemap.xml.

It is crawled and displayed in the SERP.

From a SEO point of view, would it be better to link the page in the natural flow of the website?

For example, I have 30,000 products on my website. Apart from the search results and the sitemap.xml file, there is no way to naturally link to all 30k files.

Should I develop a way to navigate to all these files by clicking alone (no search)?