You can try working your way through https://confluence.atlassian.com/display/JIRAKB/Export+More+Than+1000+Results+to+Excel but do bear in mind that the limit is set at 1000 for a reason - large exports can crash out, while destroying the performance of the system. A better approach is to examine why you want the export - in most cases, it's an ill-thought out requirement and there are better options than export and mangle in excel. (Also bear in mind that around 90% of excel sheets are, well, wrong)
I agree with Nic that you first (probably) need to find out what metric you wanted to understand with the help of this report. A raw list of 6000 test cases is not something you can get insights from...
Note: it can also help you to generate a list without further reporting assets (charts, etc.), if that's what you are primarily looking for:
Hey Community mates! Claire here from the Software Product Marketing team. We all know software development changes rapidly, and it's often tough to keep up. But from our research, we've found the h...
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