The lesson
Make the case-study index a filterable wall where every card has a short customer blurb, so a buyer can look for a customer like them.
The page headline reads 'Find out why the world's best brands choose Shopify', with a left filter panel for previous platform, industry, markets, regions and product. Below, a grid of cards shows 'Showing all 619 case studies' across 26 pages. Each card is a merchant photo, logo, a short blurb, often an outcome like Houdini's conversion lift, and category tags.
A library this size needs content you may not have, so start with a handful of cards tagged by buyer type. Keep a short outcome blurb on each card.