And why open rates matter less than you think

Email marketing is changing again. Not because people stopped using email, but because Gmail is no longer just showing emails. It is now interpreting them.

With Google’s Gemini AI built into Gmail, your email is often summarized, filtered, and ranked before a human ever decides whether to open it. That shift has big implications for how email marketing works in 2026.

Let’s break this down without the technical noise.

Gmail is no longer just a mailbox

For years, Gmail acted like a filing cabinet. Emails arrived. Users scanned subject lines. They decided what to open.

Now Gmail acts more like a smart assistant.

Gemini can:

• Summarize emails automatically
• Group and prioritize messages
• Decide which emails are likely important to the user
• Surface key information without opening the email

That means someone can understand your message without clicking into it.

Your email may be read.

Your brand may still be seen.

But the open never happens.

Why open rates are becoming a vanity metric

Open rates were always an imperfect metric, but now they are becoming even less reliable.

Here’s why:  If Gemini shows a clean summary of your email at the top of the inbox, the user may never open the message. They got the value already.

From your dashboard, it looks like:

• Lower opens
• Less engagement
• A “worse” campaign

In reality:

• Your message was delivered
• Your information was consumed
• Your brand still made an impression

You just lost visibility into the behavior.

This is very similar to what has already happened in SEO with AI Overviews. People get answers without clicking websites, which makes traditional performance metrics misleading. Email marketing is now experiencing the same shift.

How Mailchimp’s bot filtering confirms this shift

At the same time, Gmail is changing how emails are consumed, and Mailchimp is changing how engagement is measured.

Mailchimp has improved its ability to filter out non-human activity. This includes:

• Security scanners that trigger opens
• Automated inbox checks
• Bot-generated link scanning
• False engagement signals

As a result, many Mailchimp users are seeing:

• Sudden drops in open rates
• Campaigns that appear to perform worse
• Reports that feel concerning at first glance

Nothing is broken.

Mailchimp is simply showing cleaner data.

For years, open rates were inflated by automated activity. Now those fake opens are being removed while real engagement increasingly happens without an open at all due to Gemini summaries.

This creates a perfect storm where open rates drop and explain very little.

That is exactly what a vanity metric looks like.

Your real competition is no longer other brands

In the past, your email competed with other emails in the inbox.

Now it competes with:

• Gmail’s AI summaries
• Gemini’s interpretation of what matters
• An algorithm deciding which messages deserve attention

Your message has to pass two tests:

• Does Gemini think this is relevant
• Does the user still care once it is summarized

If either answer is no, your email fades into the background.

What Gmail’s AI is really prioritizing

Gmail is not trying to punish marketers. It is trying to protect users.

Gemini is likely evaluating things like:

• How often users engage with your emails
• Whether they reply, forward, or save them
• How relevant your content is over time
• Whether your emails feel personal or generic
• Whether the relationship feels real or automated

Sending more emails does not help here. In many cases, it makes things worse.

Smaller audiences will outperform bigger ones

This is one of the most important shifts happening right now.  In 2026, success will not come from having the largest list. It will come from having the most engaged list.

A smaller audience that:

• Actually expects your emails
• Reads them when they arrive
• Occasionally replies or forwards them
• Would notice if you stopped sending

Will outperform a massive list that barely pays attention.

Gemini is very good at recognizing the difference.

How email content needs to change

Here is the simple version:

• Focus on one idea per email:  Long unfocused newsletters are easy for AI to flatten and ignore.
• Get to the point quickly:  The first sentence matters more than ever. It often becomes the summary.
• Write like a person, not a campaign:  Emails that sound like marketing get treated like marketing. Emails that sound human get treated like relationships.
• Make your emails worth keeping:  If no one would search their inbox to find your email later, it is probably not strong enough.

What metrics still matter

Even though some data becomes harder to see, not everything disappears.

Metrics that still matter:

• Inbox placement and deliverability
• Spam complaints and unsubscribes
• Replies and forwards
• Long term engagement trends
• Audience health and cleanup

Metrics that matter less on their own:

• Open rates
• Short term click spikes
• Sending volume

Performance is now measured over time, not per campaign.

What smart Mailchimp users are doing now

Brands that will succeed with email marketing in 2026 are already:

• Sending fewer emails with more intention
• Segmenting more aggressively
• Archiving or removing inactive contacts
• Treating email as a relationship channel
• Focusing on usefulness instead of volume

Mailchimp’s cleaner data and Gmail’s AI both reward this approach.

The bottom line

Gmail’s Gemini is changing how success is measured in email marketing. With AI summaries and Mailchimp’s bot filtering, open rates are no longer the metric they once were.

In 2026, winning brands will focus on relevance, trust, and sending emails people actually want.

That is where Chimp Essentials helps. We help businesses build smarter Mailchimp strategies that improve engagement, strengthen deliverability, and keep your brand visible in a changing inbox.

Email still works. You just need the right strategy behind it.