Xue here from the Guru team to welcome you to Shopify and address your question!
When you're creating your Buy Button for a Collection you can adjust the number of columns with the Size picker. Here's an example from my test store:
Size: Small will yield more columns
Size: Large will yield fewer columns
You can check out our Step by Step Guide here for additional details!
If you have any other questions or concerns, please contact our Support Team at any time!
All the best,
Xue | Shopify Guru
I select the Small image size and though the preview while creating the button shows 4 columns, once you paste the script into the website it only shows two columns. It clearly a bug, since there are quite a few posts over many years.
Will this ever be fixed?