Question about mitigating large storage costs in case of ransomware

[Rob Hoelz <rob@hoelz.ro>]

Hello fellow tarsnap users!

I just started using tarsnap, and I was wondering if there exists an
option (or the potential interest in developing an option) to put a cap
on an archive size.  The reason I ask is on the off chance another
tarsnap user or I gets bitten by ransomware and it encrypts their /home
directory, I would expect the archive size for an automated backup to
really balloon in size (seeing as it's kind of hard to deduplicate and
compress random data!), and it would be nice to avoid burning through
one's account balance to add insult to injury.  Not that I intend on
getting bitten by ransomware, but you never know!

The closest thing I could find is the --maxbw option; is there a
corresponding option for archive size that I'm not seeing on the
manpage?

Thanks,
Rob