I'm absolutely perplexed at how I'm beating around the bush regarding

> a lack of backup media that isn't a HDD for storing large amounts of data indefinitely

When I recommended LTO, which you yourself say that

> LTO is perfect for this operating model

Agreed. Which is why I recommended it. As did you. Because it's a solved issue.

> * LTO drives ($3300 for an mLogic LTO-8 drive, plus media costs)

LTO-8/9 aren't the only options. LTO5/6/7 aren't defunct/unusable/unavailable. That's like complaining that SSD's are too expensive because you're only looking at Micron 9550 or Optane P5800's and their ilk.

> making it a ripe market for a competitor.

You'd have to engineer your own controllers and drives and likely cartridges as well, including drivers, firmware and software, which is neither cheap nor easy which is why no one has done this. It's doable, but the initial CapEx is astronomical, and the target market outside of enterprise is small meaning the return is unlikely to make it worth it, so you'd also have to spend big on advertising to appeal to said prosumers to try to sell them on something that most people would think of as cumbersome or obsolete ("Tape?! This isn't the 80's!", sure, we know better, but does the layman? that's not an easy sell), or find someway to make inroads against IBM/HPE/Quantum in the enterprise space which is unlikely for a not-already established big name. Even in the remote chance that they can beat IBM/HPE/Quantum on $/TB on new latest gen products, they almost certainly can't do that meaningfully cheaper than buying used Quantums from a few generations ago.

Would it be nice? Sure. In the meantime, price sensitive prosumers absolutely do not have to pay multiple thousands to get into tape storage. And if the data being backed up is truly that important, and we only limit it to new on shelf/current gen solutions, a one time (or once per decade or less) low 4 figures expense for a tape unit and media that is a fraction of HDD's $/TB value even at the cutting edge is not an unreasonable expense. Shit, people pay more than that for some QNAP/Synology junk with spinning disks and end up with less capacity and resilience with more headaches.

If the goal is "I want to back up the data on a single HDD and don't want to spend thousands to do it" the answer is to buy another HDD and mirror/clone it.

The reality is tape is still around because it already is and continues to be quite affordable (in addition to it's shelf-life/reliability), and in all likelihood (barring some breakthrough) going to outlast HDD's.

> LTO-8/9 aren't the only options. LTO5/6/7 aren't defunct/unusable/unavailable.

LTO 5 and 6 have too little capacity to be really viable these days. LTO 7 is more interesting but you're still looking at drive cost of $1000+ and media cost almost as much as HDD's per TB.