There are a few reasons why Slack may use more memory than other applications. First, Slack is a real-time messaging application that constantly checks for new messages, which requires more memory than an application that only checks for new messages periodically. Second, Slack stores all messages in memory, so that users can access them quickly and easily. This means that over time, Slack will use more and more memory as more messages are stored. Finally, Slack also stores some data in memory in order to provide a better user experience, such as user preferences and recently used files.
If you're concerned about the amount of memory Slack is using, there are a few things you can do to reduce its memory usage. First, you can try closing some of the Slack tabs or windows you have open. This will release some of the memory that Slack is using. Second, you can try clearing your Slack cache, which will remove some of the data that Slack is storing in memory. To do this, go to your Slack settings and click "Clear Cache." Finally, you can try restarting your computer, which will clear your computer's memory and may help reduce Slack's memory usage.