First, the $70/year backup is for personal use and Mac and PC only.. they do have limits, they just don't tell you what they are and they throttle even though they say they don't. The clients suck and are closed source. Also, the restore functionality is terrible.

At least with Google Drive, the 2TB plan you can store what you want and access it in the cloud like a regular file. It works with rclone and restic, so you can use it for regular backups as well and it is extremely fast. I can upload over 750GB per day in about 3 hours with Google Drive, but it would take over 3 days with Backblaze.