Dodge K-cars were well known and succesful. They were also utter shit. Plenty of FOSS projects are of low quality but get adopted because they fulfil a need. Some dont age well. Some have poor docs. Some have insufferable interfaces. It's ok to call them shit. All code is shit anyway. Its just the smell ratio that varies.
Yeah, sequoia certainly doesn't shine here either, unless you call a dump of sq https://docs.sequoia-pgp.org/sq/ help screens a useful user facing documentation.
I guess it's a nice library, but it's no replacement for GnuPG. At least GnuPG has an actual user guide, FAQ, etc. with important concepts explained step by step.
As a GnuPG user, it would not be hard to switch for simplistic use cases without any specialized HW, I guess. I already know most of the concepts, but for new users,... I wish them luck with sq, lol. Documentation is pretty much nonexistent, and the web page for sq tool just links to library documentation.