Last year my company read in excess of 20,000 tapes from just about every manufacturer and software vendor. For modern, LTO/3592/T10000 era tapes the failure rate we see is around 0.3%.

Most of these failures are due to:

cartridges being dropped or otherwise physically deformed such that they do not fit into the drives anymore.

cartridges getting stuck in drives and destructive extraction being required.

Data was never written correctly in the first place.

The only exception to this rule that we have seen is tapes written with LTFS. These tapes have a 20 fold higher incidence of failure, we believe because reading data back, as if it was a HDD, causes excessive wear.

Anyone claiming 50% failure rates on tapes has no idea what they are talking about, are reading back tapes from the 1970s/80s or have a vested interest in getting people away from tape storage.