Last week we reported that Googlebot will pretty much halt crawling and indexing websites using its desktop crawler and just crawl using its smartphone crawler (which caused a lot of confusion). But John Mueller of Google said on Reddit that he doesn't think it means you can "completely disregard what's served on desktop in terms of SEO."
John was asked, "Can I ignore the desktop version of a website due to mobile first indexing?"
John said, "All in all, I don't think it's the case that you can completely disregard what's served on desktop in terms of SEO & related."
He added that if "you had to pick one and the only reason you're running the site is for Google SEO, I'd probably pick mobile now, but it's an artificial decision, sites don't live in isolation like that, businesses do more than just Google SEO."
He did again suggest you "go responsive" when going mobile-friendly.
Here is the fully text of what he wrote:
First off, not making a responsive site in this day & age seems foreign to me. I realize sometimes things just haven't been updated in a long time and you might need to maintain it for a while, but if you're making a new site, ...Anyway.
With mobile indexing, it's true that Google focuses on the mobile version for websearch indexing. However, there are other search engines & crawlers / requestors, and there are other requests that use a desktop user-agent (I mentioned some in the recent blog post, there are also the non-search user-agents on the user-agent documentation page). All in all, I don't think it's the case that you can completely disregard what's served on desktop in terms of SEO & related. If you had to pick one and the only reason you're running the site is for Google SEO, I'd probably pick mobile now, but it's an artificial decision, sites don't live in isolation like that, businesses do more than just Google SEO (and TBH I hope you do: a healthy mix of traffic sources is good for peace of mind). And also, if you don't want to have to make this decision: go responsive.
So maybe don't ignore what is on your desktop version and going responsive does help you not have to worry about that too much.
Here is a screenshot of that discussion on Reddit, in case someone removes it:
Forum discussion at Reddit.