there are a couple tape makers, regardless of how many companies rebadge the product.
afaik, there are only 2-3 drive makers too.
but don't forget that tape doesn't make much sense (in its market) without the robotic library. there might be some off-brands that sell small libraries, but the big ones are, afaik, dominated by IBM.
I'm just talking about single drive units you manually swap tapes on. That would still make an excellent long term cold backup for me even if I did have to swap the tape s once a week but they're still 4k+ unless I go all the way down to LTO-5 tapes that are just ~1.5TB which could be good enough for critical things but not really helpful for backing up everything.