Looks like I'm a bit out of date, but older generations of LTO drives were able to read tapes from up to two generations ago, and write tapes from one generation back. Looks like this isn't the case since LTO-8. It looks for 8 and 9 theycan read and write to tapes back one generation. 10 breaks the pattern and can only read LTO-10 tapes.
https://www.lto.org/lto-generation-compatibility/