However, also for comparison, Backblaze is ~$5/TB/month.
For a backup use case, I haven't been able to beat the value of a Microsoft premium-whatever family plan. Routinely on sale for $60/yr, it gets you 1TB of backup plus an Office license for 6 users. Obviously you don't have as much control over it as "bare" cloud storage but it's hard to match the price.
AWS Glacier is ~$4/tb/month. Getting data out of there costs extra, but for backups of last resort you don't expect to ever need, that may be a workable tradeoff.
IIRC rsync.net doesn’t charge for bandwidth in any direction which for some use cases is nice - a set and forget billing type.