As the self-appointed organiser of the world's data, it makes sense that Google/Alphabet would have good data management tools for its users. And thankfully, it does, the form of Google Takeout. Anything users do on Google (photos, gmail, youtube, drive, fit, plus, etc) can be exported. Google's bots prepare your data and then email download links, or transfer the files to a linked service such as Dropbox. Download sizes can run into the multi-gigabytes.