In Excel, arrays in worksheets are limited by available random access memory, by the total number of array formulas, and by the 'entire column' rule. This article describes the limitations of arrays in Excel.
In the versions of Microsoft Excel that are listed in the 'Applies to' section, the 'Calculation Specifications' Help topic lists the limitations for working with an array. For more information about this change, read this blog post. Office 365 ProPlus is being renamed to Microsoft 365 Apps for enterprise.