Google focuses on mobile-first indexing!
This means they usually just crawl the smartphone version of your site for ranking purposes in search results.
However, I often find big differences when browsing sites through various devices, especially in SaaS.
The site may have a robust footer with links to key pages, and other features like breadcrumb trails, only viewable on desktop.
At the least, include major hub pages and perhaps an HTML sitemap link in your mobile footer. Ideally, mobile should mirror your desktop version. Ensure SEO-friendly elements like breadcrumbs and tables of contents are present, even if this requires some effort.
While it’s generally okay to hide content using accordions, content shouldn’t require interaction to load. You can test how your content is rendered using Google Search Console. Either way, you should monitor keyword rankings as ignoring hidden content may apply, though this is usually to handle spam.
These steps reduce click depth and provide yet another way for optimal internal linking. This should help your users as well, showing clear ways to access your vital content and more easily navigate your site on mobile devices too.