We are looking at going with LTO-8. The capacity and speed and the ability that it is offline and can be offsite extremely easy were all winners in our books. Offline meaning once the tape is in storage it is not on a network and can get hit by ransomware.
It's just a requirement for us. But yes, your points are valid. 12TB uncompressed per tape isn't that bad. I was looking for an upgrade because 1.5TB for LTO-5 isn't exactly what fits todays capacities.
We can't use cloud backup, hasn't been approved for us yet. So the capacity of the LTO-8 tapes is what we like.