Google added a new best practice in its crawl budget documentation to say it is best practice to ensure all links are present on the mobile version, as it is on your desktop version, if your page. If you do not do this, the discovery of new pages can be slower if the mobile version does not include all the links that are currently available on the desktop version.
What changed. Google added a new bullet point to this section of the crawl budget documentation page:
“If your site uses separate HTML for mobile and desktop versions, provide the same set of links on the mobile version as you have on the desktop version. If it’s not possible to provide the same set of links on the mobile version, ensure that they’re included in a sitemap file. Google only indexes the mobile version of pages, and limiting the links shown there can slow down discovery of new pages.”
Why Google add this. Google wrote this to explain that if you do not do this, it can slow the crawl of your mobile pages. Google wrote:
“For large websites with separate HTML on mobile and desktop versions, the discovery of new pages can be slower if the mobile version does not include all the links that are present on the desktop version.”
Why we care. If you large site uses both a mobile and desktop version of the site and the links on some of those pages do not match, it can cause discovery issues for your new content. If you want to ensure everything is optimal and the speed of crawl is fine, make sure to have the content on those pages to be the same, including the links. You can always go with a responsive design to simply this in the future.
https://searchengineland.com/google-updates-crawl-budget-docs-for-large-sites-with-differing-mobile-and-desktop-pages-and-links-447943