An even more popular alternative is Resilio Sync. I still use it because somehow sharing with the tech savvy isn't a big problem, but with the unsavvy is. A GUI and a single string is on the edge of the possible, and I share much more (large, noncode, files) with this group.
It makes sense to compare croc to wormhole because they're the same thing: PAKE-backed file transfer, where nobody has accounts, no central server holds the files, everything works from behind a NAT, all you have to is install the tool and give your counterparty an autogenerated secret password for the file.