>there are no optical disks or lto drives in my house; tis all in the cloud.
It takes a fair amount of trust to follow that kind of archival strategy. Especially with the data of the most technically sophisticated companies and governments in the world being hacked or ransomed on a daily basis.
Notwithstanding, the cloud is not a particularly practical place to upload or download the hundreds of gigabytes and terabytes we all deal with in this industry.
And circling back to the 100-year question -- all one has to do is consider number of optical drives versus LTO drives that have been sold to-date. If something like Ebay even exists in 100-years, there will easily be 10,000 used optical drives for every LTO drive being sold.
More importantly, the software that had been used to create that LTO tape -- will be long gone. And if you are lucky enough to still own a copy of that software, you'll have to run it on a computer that is under glass at the Smithsonian.
M-DISCs are admittedly limited in capacity and expensive per GB compared LTO, but they don't require any software or middleware, and they'll probably be way more readable than wire recordings and wax cylinders are today.