Looks like the major changes are:
- some stuff about Teams that's mostly only relevant if you're using your work email for a personal account
- minimium age 13 -> 18; add "Dropbox may use and rely on information from third parties, including age signals from app stores, for the purpose of enforcing this restriction."
- free accounts may be terminated after 6 months of no use (previously 12 months)
- removed "If you reside in the EU, the European Commission provides for an online dispute resolution platform, which you can access here: https://ec.europa.eu/consumers/odr." from the dispute resolution process.
That last point is funny... so arbitration agreements are designed to make the process intentionally more difficult. Can't provide too many hints!