Wasabi does have some not-entirely-true advertising on their web site though. If you don't download (which you typically don't if you're doing backups), all cloud providers are cheaper than Wasabi on per-TB-mo basis. Google Coldline or Amazon Glacier, for example, are $4 TB-mo (and Google is about to roll out $1.23 TB-mo "archive" option). Azure seems to have "archive" option for $1 TB-mo (LRS Archive option, advertises the same "11 nines", tho the price is so low, there's got to be a catch)
The Wasabi offering seems to be equivalent to the "hot" storage options, which, I agree, is crazy expensive in the cloud if you do a lot of egress.
Indeed, Wasabi is not cheap for long-term archiving of large amounts of data. It's also potentially more expensive for short-term storage because of their 90 day minimum retention period, which they explain well in their FAQ.
But they're a great fit for my personal use case of well below 1TB of rarely accessed data, while also providing peace of mind that recovery is not an issue, so I'm OK with paying more for that. Plus, it feels good betting on an underdog. :)
The Wasabi offering seems to be equivalent to the "hot" storage options, which, I agree, is crazy expensive in the cloud if you do a lot of egress.