Currently, sections with multiple columns in a marketing email are stacked on top of each other when viewing them on mobile devices. In some cases it makes sense for better readability and responsiveness.

But in some cases, you want to prevent this. Imagine adding a section with 4 text box elements at the top of your marketing email, each containing a link to a different part of your website. In fact, just like a menu.

On mobile devices, they should appear next to each other, instead of stacked. In this scenario, the marketing email becomes less mobile responsive due to bad design.
Category: Email
Ideas Administrator

Thank you for your feedback. 

We have released this feature - email editor now include a Wrap columns on mobile option for email sections. Unchecking this option for a selected section allows responsive rendering on mobile devices.. 
You may see find it here: https://docs.microsoft.com/en-us/dynamics365/marketing/whats-new-marketing#monthly-enhancements-5

PM, Microsoft