Navigating through a long list has multiple approaches depending on what your content is and how your users will interact with that content. For Azure, we group the Marketplace by Category (AI, Analytics, etc.), sub category (Bot Services, Cognitive), and then popularity (Web App Bot, Bot Channels) however the country selection drop down is usually listed alphabetically (perhaps starting with the most popular set of countries or the user's country). Both lists would have roughly a similar number of elements but are approached very differently.
For the site you linked it currently takes 3 clicks to get to any item in the directory, however the directory is the 6th (of 8) items in the nav bar (lower priority) and requires the user to scroll down before they can interact with the links you provide. The tabs work well enough if your list doesn't grow and location is important, but the location sorting theme doesn't continue in the list for each region. I might consolidate some of the sales information to make overall navigation easier but that's likely more of a business decision.