This Tool Converter Google Takeout Exports myactivity.html files to CSV so you can open in Excel, Google sheets and any CSV software.
It works and waas tested on google search, image search, video search and youtube search activity exports.
Most importantly: It's all private, personal as the upload and conversion happens in the browser and NEVER gets sent to any server nor 3rd party. (technically it's in javascript and converter in your page. Once you load the page you can even close your wifi or your internet connection and it will work)