Well thats what backups are for, but may be start with a mirror or with unimportant stuff for at least a year ;) Also proprietary service can delete your data, too. This happens especially when you are using the generous free tier and they decide to make more money. See Evernote, Gitlab, Heroku…
I‘ve actually when something like this will happen. A few years ago German energy providers and distributors needed to split, because it gives you an unfair advantage if you own both. Whole companies were split in two. People working for years together would no longer work together. In the end consumer were much better off after the split. I feel the same way with internet browser. It is unfair if you own the infrastructure (Chrome, energy grid) and the services that run on it (YouTube, power plants).