This is actually a deliberate iOS behavior that was modified in iOS 26, and you are right that it is particularly annoying. When Automatic Ear Detection is on and you remove both AirPods, iOS 26 by default resumes playback through the iPhone speaker on the assumption that you want to continue listening. This changed from earlier iOS versions where removing the AirPods would pause and keep the audio paused.
The problem is that there is currently no separate setting to control just this behavior while keeping Automatic Ear Detection active. Apple tied both behaviors together in iOS 26.
A few partial workarounds that some users have found helpful:
First, in the Podcasts app, check if there is an option under Settings within the Podcasts app itself for how audio handles device changes. Some podcast apps have their own audio session handling that can override iOS behavior.
Second, try using the iPhone's Focus modes. When you are in a meeting or quiet environment, enabling a Focus mode can suppress some background audio behaviors. This is not perfect but can reduce the frequency of accidental audio resumption.
Third, there is a way to quickly lock audio: double-press the side button on your iPhone to bring up Apple Pay, which temporarily stops audio. This is a workaround rather than a fix.
The underlying issue has been flagged by multiple users since iOS 26 launched and Apple is likely aware. Submitting feedback through Feedback Assistant (feedbackassistant.apple.com) describing the specific behavior change from iOS 18 to iOS 26 would be useful. Until Apple adds a toggle to separate ear detection from audio resumption, disabling Automatic Ear Detection remains the only complete solution unfortunately.